CINXE.COM

<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" version="XHTML+RDFa 1.0" dir="ltr" xmlns:fb="http://ogp.me/ns/fb#" xmlns:og="http://ogp.me/ns#" xmlns:article="http://ogp.me/ns/article#" xmlns:book="http://ogp.me/ns/book#" xmlns:profile="http://ogp.me/ns/profile#" xmlns:video="http://ogp.me/ns/video#" xmlns:product="http://ogp.me/ns/product#"> <head profile="http://www.w3.org/1999/xhtml/vocab"><script type="text/javascript" src="/_static/js/bundle-playback.js?v=HxkREWBo" charset="utf-8"></script> <script type="text/javascript" src="/_static/js/wombat.js?v=txqj7nKC" charset="utf-8"></script> <script>window.RufflePlayer=window.RufflePlayer||{};window.RufflePlayer.config={"autoplay":"on","unmuteOverlay":"hidden"};</script> <script type="text/javascript" src="/_static/js/ruffle/ruffle.js"></script> <script type="text/javascript"> __wm.init("https://web.archive.org/web"); __wm.wombat("https://www.drupal.org/drupalorg","20201114002552","https://web.archive.org/","web","/_static/", "1605313552"); </script> <link rel="stylesheet" type="text/css" href="/_static/css/banner-styles.css?v=S1zqJCYt" /> <link rel="stylesheet" type="text/css" href="/_static/css/iconochive.css?v=3PDvdIFv" />  <meta name="HandheldFriendly" content="true"/> <meta name="viewport" content="width=device-width"/> <meta name="MobileOptimized" content="width"/>  <link rel="dns-prefetch" href="//web.archive.org/web/20201114002552/https://fonts.googleapis.com/"/> <link rel="preconnect" href="//web.archive.org/web/20201114002552/https://fonts.gstatic.com/" crossorigin=""/> <link rel="dns-prefetch" href="//web.archive.org/web/20201114002552/https://fonts.gstatic.com/"/> <link rel="preconnect" href="//web.archive.org/web/20201114002552/https://fonts.googleapis.com/"/> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><script type="text/javascript">(window.NREUM||(NREUM={})).loader_config={xpid:"XAcEV19XGwcCUldTDwg=",licenseKey:"e671e25255",applicationID:"4266189"};window.NREUM||(NREUM={}),__nr_require=function(t,e,n){function r(n){if(!e[n]){var i=e[n]={exports:{}};t[n][0].call(i.exports,function(e){var i=t[n][1][e];return r(i||e)},i,i.exports)}return e[n].exports}if("function"==typeof __nr_require)return __nr_require;for(var i=0;i<n.length;i++)r(n[i]);return r}({1:[function(t,e,n){function r(t){try{c.console&&console.log(t)}catch(e){}}var i,o=t("ee"),a=t(23),c={};try{i=localStorage.getItem("__nr_flags").split(","),console&&"function"==typeof console.log&&(c.console=!0,i.indexOf("dev")!==-1&&(c.dev=!0),i.indexOf("nr_dev")!==-1&&(c.nrDev=!0))}catch(s){}c.nrDev&&o.on("internal-error",function(t){r(t.stack)}),c.dev&&o.on("fn-err",function(t,e,n){r(n.stack)}),c.dev&&(r("NR AGENT IN DEVELOPMENT MODE"),r("flags: "+a(c,function(t,e){return t}).join(", ")))},{}],2:[function(t,e,n){function r(t,e,n,r,c){try{p?p-=1:i(c||new UncaughtException(t,e,n),!0)}catch(f){try{o("ierr",[f,s.now(),!0])}catch(d){}}return"function"==typeof u&&u.apply(this,a(arguments))}function UncaughtException(t,e,n){this.message=t||"Uncaught error with no additional information",this.sourceURL=e,this.line=n}function i(t,e){var n=e?null:s.now();o("err",[t,n])}var o=t("handle"),a=t(24),c=t("ee"),s=t("loader"),f=t("gos"),u=window.onerror,d=!1,l="nr@seenError",p=0;s.features.err=!0,t(1),window.onerror=r;try{throw new Error}catch(h){"stack"in h&&(t(9),t(8),"addEventListener"in window&&t(5),s.xhrWrappable&&t(10),d=!0)}c.on("fn-start",function(t,e,n){d&&(p+=1)}),c.on("fn-err",function(t,e,n){d&&!n[l]&&(f(n,l,function(){return!0}),this.thrown=!0,i(n))}),c.on("fn-end",function(){d&&!this.thrown&&p>0&&(p-=1)}),c.on("internal-error",function(t){o("ierr",[t,s.now(),!0])})},{}],3:[function(t,e,n){t("loader").features.ins=!0},{}],4:[function(t,e,n){function r(t){}if(window.performance&&window.performance.timing&&window.performance.getEntriesByType){var i=t("ee"),o=t("handle"),a=t(9),c=t(8),s="learResourceTimings",f="addEventListener",u="resourcetimingbufferfull",d="bstResource",l="resource",p="-start",h="-end",m="fn"+p,w="fn"+h,v="bstTimer",g="pushState",y=t("loader");y.features.stn=!0,t(7),"addEventListener"in window&&t(5);var x=NREUM.o.EV;i.on(m,function(t,e){var n=t[0];n instanceof x&&(this.bstStart=y.now())}),i.on(w,function(t,e){var n=t[0];n instanceof x&&o("bst",[n,e,this.bstStart,y.now()])}),a.on(m,function(t,e,n){this.bstStart=y.now(),this.bstType=n}),a.on(w,function(t,e){o(v,[e,this.bstStart,y.now(),this.bstType])}),c.on(m,function(){this.bstStart=y.now()}),c.on(w,function(t,e){o(v,[e,this.bstStart,y.now(),"requestAnimationFrame"])}),i.on(g+p,function(t){this.time=y.now(),this.startPath=location.pathname+location.hash}),i.on(g+h,function(t){o("bstHist",[location.pathname+location.hash,this.startPath,this.time])}),f in window.performance&&(window.performance["c"+s]?window.performance[f](u,function(t){o(d,[window.performance.getEntriesByType(l)]),window.performance["c"+s]()},!1):window.performance[f]("webkit"+u,function(t){o(d,[window.performance.getEntriesByType(l)]),window.performance["webkitC"+s]()},!1)),document[f]("scroll",r,{passive:!0}),document[f]("keypress",r,!1),document[f]("click",r,!1)}},{}],5:[function(t,e,n){function r(t){for(var e=t;e&&!e.hasOwnProperty(u);)e=Object.getPrototypeOf(e);e&&i(e)}function i(t){c.inPlace(t,[u,d],"-",o)}function o(t,e){return t[1]}var a=t("ee").get("events"),c=t("wrap-function")(a,!0),s=t("gos"),f=XMLHttpRequest,u="addEventListener",d="removeEventListener";e.exports=a,"getPrototypeOf"in Object?(r(document),r(window),r(f.prototype)):f.prototype.hasOwnProperty(u)&&(i(window),i(f.prototype)),a.on(u+"-start",function(t,e){var n=t[1],r=s(n,"nr@wrapped",function(){function t(){if("function"==typeof n.handleEvent)return n.handleEvent.apply(n,arguments)}var e={object:t,"function":n}[typeof n];return e?c(e,"fn-",null,e.name||"anonymous"):n});this.wrapped=t[1]=r}),a.on(d+"-start",function(t){t[1]=this.wrapped||t[1]})},{}],6:[function(t,e,n){function r(t,e,n){var r=t[e];"function"==typeof r&&(t[e]=function(){var t=o(arguments),e={};i.emit(n+"before-start",[t],e);var a;e[m]&&e[m].dt&&(a=e[m].dt);var c=r.apply(this,t);return i.emit(n+"start",[t,a],c),c.then(function(t){return i.emit(n+"end",[null,t],c),t},function(t){throw i.emit(n+"end",[t],c),t})})}var i=t("ee").get("fetch"),o=t(24),a=t(23);e.exports=i;var c=window,s="fetch-",f=s+"body-",u=["arrayBuffer","blob","json","text","formData"],d=c.Request,l=c.Response,p=c.fetch,h="prototype",m="nr@context";d&&l&&p&&(a(u,function(t,e){r(d[h],e,f),r(l[h],e,f)}),r(c,"fetch",s),i.on(s+"end",function(t,e){var n=this;if(e){var r=e.headers.get("content-length");null!==r&&(n.rxSize=r),i.emit(s+"done",[null,e],n)}else i.emit(s+"done",[t],n)}))},{}],7:[function(t,e,n){var r=t("ee").get("history"),i=t("wrap-function")(r);e.exports=r;var o=window.history&&window.history.constructor&&window.history.constructor.prototype,a=window.history;o&&o.pushState&&o.replaceState&&(a=o),i.inPlace(a,["pushState","replaceState"],"-")},{}],8:[function(t,e,n){var r=t("ee").get("raf"),i=t("wrap-function")(r),o="equestAnimationFrame";e.exports=r,i.inPlace(window,["r"+o,"mozR"+o,"webkitR"+o,"msR"+o],"raf-"),r.on("raf-start",function(t){t[0]=i(t[0],"fn-")})},{}],9:[function(t,e,n){function r(t,e,n){t[0]=a(t[0],"fn-",null,n)}function i(t,e,n){this.method=n,this.timerDuration=isNaN(t[1])?0:+t[1],t[0]=a(t[0],"fn-",this,n)}var o=t("ee").get("timer"),a=t("wrap-function")(o),c="setTimeout",s="setInterval",f="clearTimeout",u="-start",d="-";e.exports=o,a.inPlace(window,[c,"setImmediate"],c+d),a.inPlace(window,[s],s+d),a.inPlace(window,[f,"clearImmediate"],f+d),o.on(s+u,r),o.on(c+u,i)},{}],10:[function(t,e,n){function r(t,e){d.inPlace(e,["onreadystatechange"],"fn-",c)}function i(){var t=this,e=u.context(t);t.readyState>3&&!e.resolved&&(e.resolved=!0,u.emit("xhr-resolved",[],t)),d.inPlace(t,g,"fn-",c)}function o(t){y.push(t),h&&(b?b.then(a):w?w(a):(E=-E,R.data=E))}function a(){for(var t=0;t<y.length;t++)r([],y[t]);y.length&&(y=[])}function c(t,e){return e}function s(t,e){for(var n in t)e[n]=t[n];return e}t(5);var f=t("ee"),u=f.get("xhr"),d=t("wrap-function")(u),l=NREUM.o,p=l.XHR,h=l.MO,m=l.PR,w=l.SI,v="readystatechange",g=["onload","onerror","onabort","onloadstart","onloadend","onprogress","ontimeout"],y=[];e.exports=u;var x=window.XMLHttpRequest=function(t){var e=new p(t);try{u.emit("new-xhr",[e],e),e.addEventListener(v,i,!1)}catch(n){try{u.emit("internal-error",[n])}catch(r){}}return e};if(s(p,x),x.prototype=p.prototype,d.inPlace(x.prototype,["open","send"],"-xhr-",c),u.on("send-xhr-start",function(t,e){r(t,e),o(e)}),u.on("open-xhr-start",r),h){var b=m&&m.resolve();if(!w&&!m){var E=1,R=document.createTextNode(E);new h(a).observe(R,{characterData:!0})}}else f.on("fn-end",function(t){t[0]&&t[0].type===v||a()})},{}],11:[function(t,e,n){function r(t){if(!c(t))return null;var e=window.NREUM;if(!e.loader_config)return null;var n=(e.loader_config.accountID||"").toString()||null,r=(e.loader_config.agentID||"").toString()||null,f=(e.loader_config.trustKey||"").toString()||null;if(!n||!r)return null;var h=p.generateSpanId(),m=p.generateTraceId(),w=Date.now(),v={spanId:h,traceId:m,timestamp:w};return(t.sameOrigin||s(t)&&l())&&(v.traceContextParentHeader=i(h,m),v.traceContextStateHeader=o(h,w,n,r,f)),(t.sameOrigin&&!u()||!t.sameOrigin&&s(t)&&d())&&(v.newrelicHeader=a(h,m,w,n,r,f)),v}function i(t,e){return"00-"+e+"-"+t+"-01"}function o(t,e,n,r,i){var o=0,a="",c=1,s="",f="";return i+"@nr="+o+"-"+c+"-"+n+"-"+r+"-"+t+"-"+a+"-"+s+"-"+f+"-"+e}function a(t,e,n,r,i,o){var a="btoa"in window&&"function"==typeof window.btoa;if(!a)return null;var c={v:[0,1],d:{ty:"Browser",ac:r,ap:i,id:t,tr:e,ti:n}};return o&&r!==o&&(c.d.tk=o),btoa(JSON.stringify(c))}function c(t){return f()&&s(t)}function s(t){var e=!1,n={};if("init"in NREUM&&"distributed_tracing"in NREUM.init&&(n=NREUM.init.distributed_tracing),t.sameOrigin)e=!0;else if(n.allowed_origins instanceof Array)for(var r=0;r<n.allowed_origins.length;r++){var i=h(n.allowed_origins[r]);if(t.hostname===i.hostname&&t.protocol===i.protocol&&t.port===i.port){e=!0;break}}return e}function f(){return"init"in NREUM&&"distributed_tracing"in NREUM.init&&!!NREUM.init.distributed_tracing.enabled}function u(){return"init"in NREUM&&"distributed_tracing"in NREUM.init&&!!NREUM.init.distributed_tracing.exclude_newrelic_header}function d(){return"init"in NREUM&&"distributed_tracing"in NREUM.init&&NREUM.init.distributed_tracing.cors_use_newrelic_header!==!1}function l(){return"init"in NREUM&&"distributed_tracing"in NREUM.init&&!!NREUM.init.distributed_tracing.cors_use_tracecontext_headers}var p=t(20),h=t(13);e.exports={generateTracePayload:r,shouldGenerateTrace:c}},{}],12:[function(t,e,n){function r(t){var e=this.params,n=this.metrics;if(!this.ended){this.ended=!0;for(var r=0;r<l;r++)t.removeEventListener(d[r],this.listener,!1);e.aborted||(n.duration=a.now()-this.startTime,this.loadCaptureCalled||4!==t.readyState?null==e.status&&(e.status=0):o(this,t),n.cbTime=this.cbTime,u.emit("xhr-done",[t],t),c("xhr",[e,n,this.startTime]))}}function i(t,e){var n=s(e),r=t.params;r.host=n.hostname+":"+n.port,r.pathname=n.pathname,t.parsedOrigin=s(e),t.sameOrigin=t.parsedOrigin.sameOrigin}function o(t,e){t.params.status=e.status;var n=w(e,t.lastSize);if(n&&(t.metrics.rxSize=n),t.sameOrigin){var r=e.getResponseHeader("X-NewRelic-App-Data");r&&(t.params.cat=r.split(", ").pop())}t.loadCaptureCalled=!0}var a=t("loader");if(a.xhrWrappable){var c=t("handle"),s=t(13),f=t(11).generateTracePayload,u=t("ee"),d=["load","error","abort","timeout"],l=d.length,p=t("id"),h=t(17),m=t(16),w=t(14),v=window.XMLHttpRequest;a.features.xhr=!0,t(10),t(6),u.on("new-xhr",function(t){var e=this;e.totalCbs=0,e.called=0,e.cbTime=0,e.end=r,e.ended=!1,e.xhrGuids={},e.lastSize=null,e.loadCaptureCalled=!1,t.addEventListener("load",function(n){o(e,t)},!1),h&&(h>34||h<10)||window.opera||t.addEventListener("progress",function(t){e.lastSize=t.loaded},!1)}),u.on("open-xhr-start",function(t){this.params={method:t[0]},i(this,t[1]),this.metrics={}}),u.on("open-xhr-end",function(t,e){"loader_config"in NREUM&&"xpid"in NREUM.loader_config&&this.sameOrigin&&e.setRequestHeader("X-NewRelic-ID",NREUM.loader_config.xpid);var n=f(this.parsedOrigin);if(n){var r=!1;n.newrelicHeader&&(e.setRequestHeader("newrelic",n.newrelicHeader),r=!0),n.traceContextParentHeader&&(e.setRequestHeader("traceparent",n.traceContextParentHeader),n.traceContextStateHeader&&e.setRequestHeader("tracestate",n.traceContextStateHeader),r=!0),r&&(this.dt=n)}}),u.on("send-xhr-start",function(t,e){var n=this.metrics,r=t[0],i=this;if(n&&r){var o=m(r);o&&(n.txSize=o)}this.startTime=a.now(),this.listener=function(t){try{"abort"!==t.type||i.loadCaptureCalled||(i.params.aborted=!0),("load"!==t.type||i.called===i.totalCbs&&(i.onloadCalled||"function"!=typeof e.onload))&&i.end(e)}catch(n){try{u.emit("internal-error",[n])}catch(r){}}};for(var c=0;c<l;c++)e.addEventListener(d[c],this.listener,!1)}),u.on("xhr-cb-time",function(t,e,n){this.cbTime+=t,e?this.onloadCalled=!0:this.called+=1,this.called!==this.totalCbs||!this.onloadCalled&&"function"==typeof n.onload||this.end(n)}),u.on("xhr-load-added",function(t,e){var n=""+p(t)+!!e;this.xhrGuids&&!this.xhrGuids[n]&&(this.xhrGuids[n]=!0,this.totalCbs+=1)}),u.on("xhr-load-removed",function(t,e){var n=""+p(t)+!!e;this.xhrGuids&&this.xhrGuids[n]&&(delete this.xhrGuids[n],this.totalCbs-=1)}),u.on("addEventListener-end",function(t,e){e instanceof v&&"load"===t[0]&&u.emit("xhr-load-added",[t[1],t[2]],e)}),u.on("removeEventListener-end",function(t,e){e instanceof v&&"load"===t[0]&&u.emit("xhr-load-removed",[t[1],t[2]],e)}),u.on("fn-start",function(t,e,n){e instanceof v&&("onload"===n&&(this.onload=!0),("load"===(t[0]&&t[0].type)||this.onload)&&(this.xhrCbStart=a.now()))}),u.on("fn-end",function(t,e){this.xhrCbStart&&u.emit("xhr-cb-time",[a.now()-this.xhrCbStart,this.onload,e],e)}),u.on("fetch-before-start",function(t){function e(t,e){var n=!1;return e.newrelicHeader&&(t.set("newrelic",e.newrelicHeader),n=!0),e.traceContextParentHeader&&(t.set("traceparent",e.traceContextParentHeader),e.traceContextStateHeader&&t.set("tracestate",e.traceContextStateHeader),n=!0),n}var n,r=t[1]||{};"string"==typeof t[0]?n=t[0]:t[0]&&t[0].url&&(n=t[0].url),n&&(this.parsedOrigin=s(n),this.sameOrigin=this.parsedOrigin.sameOrigin);var i=f(this.parsedOrigin);if(i&&(i.newrelicHeader||i.traceContextParentHeader))if("string"==typeof t[0]){var o={};for(var a in r)o[a]=r[a];o.headers=new Headers(r.headers||{}),e(o.headers,i)&&(this.dt=i),t.length>1?t[1]=o:t.push(o)}else t[0]&&t[0].headers&&e(t[0].headers,i)&&(this.dt=i)})}},{}],13:[function(t,e,n){var r={};e.exports=function(t){if(t in r)return r[t];var e=document.createElement("a"),n=window.location,i={};e.href=t,i.port=e.port;var o=e.href.split("://");!i.port&&o[1]&&(i.port=o[1].split("/")[0].split("@").pop().split(":")[1]),i.port&&"0"!==i.port||(i.port="https"===o[0]?"443":"80"),i.hostname=e.hostname||n.hostname,i.pathname=e.pathname,i.protocol=o[0],"/"!==i.pathname.charAt(0)&&(i.pathname="/"+i.pathname);var a=!e.protocol||":"===e.protocol||e.protocol===n.protocol,c=e.hostname===document.domain&&e.port===n.port;return i.sameOrigin=a&&(!e.hostname||c),"/"===i.pathname&&(r[t]=i),i}},{}],14:[function(t,e,n){function r(t,e){var n=t.responseType;return"json"===n&&null!==e?e:"arraybuffer"===n||"blob"===n||"json"===n?i(t.response):"text"===n||""===n||void 0===n?i(t.responseText):void 0}var i=t(16);e.exports=r},{}],15:[function(t,e,n){function r(){}function i(t,e,n){return function(){return o(t,[f.now()].concat(c(arguments)),e?null:this,n),e?void 0:this}}var o=t("handle"),a=t(23),c=t(24),s=t("ee").get("tracer"),f=t("loader"),u=NREUM;"undefined"==typeof window.newrelic&&(newrelic=u);var d=["setPageViewName","setCustomAttribute","setErrorHandler","finished","addToTrace","inlineHit","addRelease"],l="api-",p=l+"ixn-";a(d,function(t,e){u[e]=i(l+e,!0,"api")}),u.addPageAction=i(l+"addPageAction",!0),u.setCurrentRouteName=i(l+"routeName",!0),e.exports=newrelic,u.interaction=function(){return(new r).get()};var h=r.prototype={createTracer:function(t,e){var n={},r=this,i="function"==typeof e;return o(p+"tracer",[f.now(),t,n],r),function(){if(s.emit((i?"":"no-")+"fn-start",[f.now(),r,i],n),i)try{return e.apply(this,arguments)}catch(t){throw s.emit("fn-err",[arguments,this,t],n),t}finally{s.emit("fn-end",[f.now()],n)}}}};a("actionText,setName,setAttribute,save,ignore,onEnd,getContext,end,get".split(","),function(t,e){h[e]=i(p+e)}),newrelic.noticeError=function(t,e){"string"==typeof t&&(t=new Error(t)),o("err",[t,f.now(),!1,e])}},{}],16:[function(t,e,n){e.exports=function(t){if("string"==typeof t&&t.length)return t.length;if("object"==typeof t){if("undefined"!=typeof ArrayBuffer&&t instanceof ArrayBuffer&&t.byteLength)return t.byteLength;if("undefined"!=typeof Blob&&t instanceof Blob&&t.size)return t.size;if(!("undefined"!=typeof FormData&&t instanceof FormData))try{return JSON.stringify(t).length}catch(e){return}}}},{}],17:[function(t,e,n){var r=0,i=navigator.userAgent.match(/Firefox[\/\s](\d+\.\d+)/);i&&(r=+i[1]),e.exports=r},{}],18:[function(t,e,n){function r(){return c.exists&&performance.now?Math.round(performance.now()):(o=Math.max((new Date).getTime(),o))-a}function i(){return o}var o=(new Date).getTime(),a=o,c=t(25);e.exports=r,e.exports.offset=a,e.exports.getLastTimestamp=i},{}],19:[function(t,e,n){function r(t,e){var n=t.getEntries();n.forEach(function(t){"first-paint"===t.name?d("timing",["fp",Math.floor(t.startTime)]):"first-contentful-paint"===t.name&&d("timing",["fcp",Math.floor(t.startTime)])})}function i(t,e){var n=t.getEntries();n.length>0&&d("lcp",[n[n.length-1]])}function o(t){t.getEntries().forEach(function(t){t.hadRecentInput||d("cls",[t])})}function a(t){if(t instanceof h&&!w){var e=Math.round(t.timeStamp),n={type:t.type};e<=l.now()?n.fid=l.now()-e:e>l.offset&&e<=Date.now()?(e-=l.offset,n.fid=l.now()-e):e=l.now(),w=!0,d("timing",["fi",e,n])}}function c(t){d("pageHide",[l.now(),t])}if(!("init"in NREUM&&"page_view_timing"in NREUM.init&&"enabled"in NREUM.init.page_view_timing&&NREUM.init.page_view_timing.enabled===!1)){var s,f,u,d=t("handle"),l=t("loader"),p=t(22),h=NREUM.o.EV;if("PerformanceObserver"in window&&"function"==typeof window.PerformanceObserver){s=new PerformanceObserver(r);try{s.observe({entryTypes:["paint"]})}catch(m){}f=new PerformanceObserver(i);try{f.observe({entryTypes:["largest-contentful-paint"]})}catch(m){}u=new PerformanceObserver(o);try{u.observe({type:"layout-shift",buffered:!0})}catch(m){}}if("addEventListener"in document){var w=!1,v=["click","keydown","mousedown","pointerdown","touchstart"];v.forEach(function(t){document.addEventListener(t,a,!1)})}p(c)}},{}],20:[function(t,e,n){function r(){function t(){return e?15&e[n++]:16*Math.random()|0}var e=null,n=0,r=window.crypto||window.msCrypto;r&&r.getRandomValues&&(e=r.getRandomValues(new Uint8Array(31)));for(var i,o="xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx",a="",c=0;c<o.length;c++)i=o[c],"x"===i?a+=t().toString(16):"y"===i?(i=3&t()|8,a+=i.toString(16)):a+=i;return a}function i(){return a(16)}function o(){return a(32)}function a(t){function e(){return n?15&n[r++]:16*Math.random()|0}var n=null,r=0,i=window.crypto||window.msCrypto;i&&i.getRandomValues&&Uint8Array&&(n=i.getRandomValues(new Uint8Array(31)));for(var o=[],a=0;a<t;a++)o.push(e().toString(16));return o.join("")}e.exports={generateUuid:r,generateSpanId:i,generateTraceId:o}},{}],21:[function(t,e,n){function r(t,e){if(!i)return!1;if(t!==i)return!1;if(!e)return!0;if(!o)return!1;for(var n=o.split("."),r=e.split("."),a=0;a<r.length;a++)if(r[a]!==n[a])return!1;return!0}var i=null,o=null,a=/Version\/(\S+)\s+Safari/;if(navigator.userAgent){var c=navigator.userAgent,s=c.match(a);s&&c.indexOf("Chrome")===-1&&c.indexOf("Chromium")===-1&&(i="Safari",o=s[1])}e.exports={agent:i,version:o,match:r}},{}],22:[function(t,e,n){function r(t){function e(){t(a&&document[a]?document[a]:document[i]?"hidden":"visible")}"addEventListener"in document&&o&&document.addEventListener(o,e,!1)}e.exports=r;var i,o,a;"undefined"!=typeof document.hidden?(i="hidden",o="visibilitychange",a="visibilityState"):"undefined"!=typeof document.msHidden?(i="msHidden",o="msvisibilitychange"):"undefined"!=typeof document.webkitHidden&&(i="webkitHidden",o="webkitvisibilitychange",a="webkitVisibilityState")},{}],23:[function(t,e,n){function r(t,e){var n=[],r="",o=0;for(r in t)i.call(t,r)&&(n[o]=e(r,t[r]),o+=1);return n}var i=Object.prototype.hasOwnProperty;e.exports=r},{}],24:[function(t,e,n){function r(t,e,n){e||(e=0),"undefined"==typeof n&&(n=t?t.length:0);for(var r=-1,i=n-e||0,o=Array(i<0?0:i);++r<i;)o[r]=t[e+r];return o}e.exports=r},{}],25:[function(t,e,n){e.exports={exists:"undefined"!=typeof window.performance&&window.performance.timing&&"undefined"!=typeof window.performance.timing.navigationStart}},{}],ee:[function(t,e,n){function r(){}function i(t){function e(t){return t&&t instanceof r?t:t?s(t,c,o):o()}function n(n,r,i,o){if(!l.aborted||o){t&&t(n,r,i);for(var a=e(i),c=m(n),s=c.length,f=0;f<s;f++)c[f].apply(a,r);var d=u[y[n]];return d&&d.push([x,n,r,a]),a}}function p(t,e){g[t]=m(t).concat(e)}function h(t,e){var n=g[t];if(n)for(var r=0;r<n.length;r++)n[r]===e&&n.splice(r,1)}function m(t){return g[t]||[]}function w(t){return d[t]=d[t]||i(n)}function v(t,e){f(t,function(t,n){e=e||"feature",y[n]=e,e in u||(u[e]=[])})}var g={},y={},x={on:p,addEventListener:p,removeEventListener:h,emit:n,get:w,listeners:m,context:e,buffer:v,abort:a,aborted:!1};return x}function o(){return new r}function a(){(u.api||u.feature)&&(l.aborted=!0,u=l.backlog={})}var c="nr@context",s=t("gos"),f=t(23),u={},d={},l=e.exports=i();l.backlog=u},{}],gos:[function(t,e,n){function r(t,e,n){if(i.call(t,e))return t[e];var r=n();if(Object.defineProperty&&Object.keys)try{return Object.defineProperty(t,e,{value:r,writable:!0,enumerable:!1}),r}catch(o){}return t[e]=r,r}var i=Object.prototype.hasOwnProperty;e.exports=r},{}],handle:[function(t,e,n){function r(t,e,n,r){i.buffer([t],r),i.emit(t,e,n)}var i=t("ee").get("handle");e.exports=r,r.ee=i},{}],id:[function(t,e,n){function r(t){var e=typeof t;return!t||"object"!==e&&"function"!==e?-1:t===window?0:a(t,o,function(){return i++})}var i=1,o="nr@id",a=t("gos");e.exports=r},{}],loader:[function(t,e,n){function r(){if(!b++){var t=x.info=NREUM.info,e=l.getElementsByTagName("script")[0];if(setTimeout(f.abort,3e4),!(t&&t.licenseKey&&t.applicationID&&e))return f.abort();s(g,function(e,n){t[e]||(t[e]=n)});var n=a();c("mark",["onload",n+x.offset],null,"api"),c("timing",["load",n]);var r=l.createElement("script");r.src="https://"+t.agent,e.parentNode.insertBefore(r,e)}}function i(){"complete"===l.readyState&&o()}function o(){c("mark",["domContent",a()+x.offset],null,"api")}var a=t(18),c=t("handle"),s=t(23),f=t("ee"),u=t(21),d=window,l=d.document,p="addEventListener",h="attachEvent",m=d.XMLHttpRequest,w=m&&m.prototype;NREUM.o={ST:setTimeout,SI:d.setImmediate,CT:clearTimeout,XHR:m,REQ:d.Request,EV:d.Event,PR:d.Promise,MO:d.MutationObserver};var v=""+location,g={beacon:"bam.nr-data.net",errorBeacon:"bam.nr-data.net",agent:"js-agent.newrelic.com/nr-1184.min.js"},y=m&&w&&w[p]&&!/CriOS/.test(navigator.userAgent),x=e.exports={offset:a.getLastTimestamp(),now:a,origin:v,features:{},xhrWrappable:y,userAgent:u};t(15),t(19),l[p]?(l[p]("DOMContentLoaded",o,!1),d[p]("load",r,!1)):(l[h]("onreadystatechange",i),d[h]("onload",r)),c("mark",["firstbyte",a.getLastTimestamp()],null,"api");var b=0},{}],"wrap-function":[function(t,e,n){function r(t){return!(t&&t instanceof Function&&t.apply&&!t[a])}var i=t("ee"),o=t(24),a="nr@original",c=Object.prototype.hasOwnProperty,s=!1;e.exports=function(t,e){function n(t,e,n,i){function nrWrapper(){var r,a,c,s;try{a=this,r=o(arguments),c="function"==typeof n?n(r,a):n||{}}catch(f){l([f,"",[r,a,i],c])}u(e+"start",[r,a,i],c);try{return s=t.apply(a,r)}catch(d){throw u(e+"err",[r,a,d],c),d}finally{u(e+"end",[r,a,s],c)}}return r(t)?t:(e||(e=""),nrWrapper[a]=t,d(t,nrWrapper),nrWrapper)}function f(t,e,i,o){i||(i="");var a,c,s,f="-"===i.charAt(0);for(s=0;s<e.length;s++)c=e[s],a=t[c],r(a)||(t[c]=n(a,f?c+i:i,o,c))}function u(n,r,i){if(!s||e){var o=s;s=!0;try{t.emit(n,r,i,e)}catch(a){l([a,n,r,i])}s=o}}function d(t,e){if(Object.defineProperty&&Object.keys)try{var n=Object.keys(t);return n.forEach(function(n){Object.defineProperty(e,n,{get:function(){return t[n]},set:function(e){return t[n]=e,e}})}),e}catch(r){l([r])}for(var i in t)c.call(t,i)&&(e[i]=t[i]);return e}function l(e){try{t.emit("internal-error",e)}catch(n){}}return t||(t=i),n.inPlace=f,n.flag=a,n}},{}]},{},["loader",2,12,4,3]);</script> <meta name="description" content="Drupal.org is a home of the Drupal project and the Drupal community. It is supported and maintained by the Drupal Association with the help of the Drupal community volunteers. Created in 2001, it is one of the largest, continuously operating examples of Drupal."/> <meta name="generator" content="Drupal 7 (https://www.drupal.org)"/> <link rel="canonical" href="https://web.archive.org/web/20201114002552/https://www.drupal.org/drupalorg"/> <link rel="shortlink" href="https://web.archive.org/web/20201114002552/https://www.drupal.org/node/2580639"/> <meta property="og:site_name" content="Drupal.org"/> <meta property="og:type" content="article"/> <meta property="og:url" content="https://web.archive.org/web/20201114002552/https://www.drupal.org/drupalorg"/> <meta property="og:title" content="Drupal.org"/> <meta property="og:description" content="Drupal.org is a home of the Drupal project and the Drupal community. It is supported and maintained by the Drupal Association with the help of the Drupal community volunteers. Created in 2001, it is one of the largest, continuously operating examples of Drupal."/> <meta property="og:updated_time" content="2017-01-13T16:13:38+00:00"/> <meta property="article:published_time" content="2015-10-05T20:17:49+00:00"/> <meta property="article:modified_time" content="2017-01-13T16:13:38+00:00"/> <title>Drupal.org | Drupal.org</title> <link type="text/css" rel="stylesheet" href="/web/20201114002552cs_/https://www.drupal.org/files/advagg_css/css__FN2RTiB3W78YZgXvD7kGMoWo3ufXBV345Z1UG8yvZFE__XMJmLtgfFjPsRFf-TTMt1ejFpXBEo_Fip05xPtaPoAE__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.css" media="all"/> <link type="text/css" rel="stylesheet" href="/web/20201114002552cs_/https://www.drupal.org/files/advagg_css/css__eFKSCujfWyJYO8J-qSi6T_n29lROS8isvrxzANeHaAY__D_EUHDAfEQdxcLiSDY7hREUWkG1Ge56_h2z3Er8V188__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.css" media="all"/> <link type="text/css" rel="stylesheet" href="/web/20201114002552cs_/https://www.drupal.org/files/advagg_css/css__mXUsFOkFX1Vp3cPaBtPrMNLiyy4rOzIAVz7DppnovsY__4a32sD5wTTMzrJf7XqA8yck7wVaHdAmb-RLMBilVXyY__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.css" media="all"/> <link type="text/css" rel="stylesheet" href="/web/20201114002552cs_/https://www.drupal.org/files/advagg_css/css__WF0PRotZAhCcl0aJjY5W2LYj8UwiYuB2dZEFluOh3Tc__FviX13FUB-Ppa2XB29BUIJQZ1Wg-F5XiDE7XD5y7mjQ__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.css" media="all"/> <link type="text/css" rel="stylesheet" href="/web/20201114002552cs_/https://www.drupal.org/files/advagg_css/css__Fx0_w1L9q3nwzXnALG7UfjLF34FGYgJTz636-GWbM6k__0jWLTEHP3h5U5RcXuZcFhf0DdvRdzP3_wzCVNT015Ls__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.css" media="all"/> <link type="text/css" rel="stylesheet" href="/web/20201114002552cs_/https://www.drupal.org/files/advagg_css/css__QPp1snPjYt_xYr0c_V0IORcEElkIUBBBrvOB4ZE0Gnw__AXRXftWrkPpt9EgcCtXXbq1c3CwV2RvR80wyEoQ15jY__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.css" media="all"/> </head> <body class="html not-front not-logged-in no-sidebars page-node page-node- page-node-2580639 node-type-section drupalorg-site-main panels-layout new-style og-context og-context-node og-context-node-2580639"> <div id="skip-link" tabindex="-1"> <a class="element-invisible element-focusable" href="#content">Skip to main content</a> <a class="element-invisible element-focusable skip-link-search" href="#search-block-form">Skip to search</a> </div> <div class="region region-page-top"> <noscript aria-hidden="true"><iframe src="https://web.archive.org/web/20201114002552if_/https://www.googletagmanager.com/ns.html?id=GTM-W36H8DW" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <div id="drupalorg-crosssite-gdpr">Can we use first and third party cookies and web beacons to <a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/terms">understand our audience, and to tailor promotions you see</a>?<br><button class="yes">Yes, please</button><button class="no">No, do not track me</button></div> </div> <div id="nav-header"> <div class="menu-nav"> <a class="nav-btn" id="nav-open-btn" href="#block-system-main-menu"><img src="/web/20201114002552im_/https://www.drupal.org/sites/all/themes/bluecheese/images/icon-w-menu.svg" alt="Main menu"></a> </div> <nav id="navigation-inner" class="container-12" role="navigation"> <div class="region region-navigation"> <div id="block-system-main-menu" class="block block-system block-menu"> <div class="block-inner"> <div class="content"> <div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/home" title="Drupal.org home page">Drupal.org home</a></li> <li class="expanded"><a href="/web/20201114002552/https://www.drupal.org/about" title="">Why Drupal?</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/developers" title="">For developers</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/marketers" title="Why marketers should choose Drupal for their ambitious digital experiences">For marketers</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/agencies" title="Learn why agencies are betting their future on Drupal">For agencies</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/case-studies" title="View case studies to see how your peers have built success on Drupal">Case studies</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/about" title="Learn about Drupal">About Drupal</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/about/9" title="Prepare for Drupal 9">Drupal 9</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/about/in-the-news" title="">In the news</a></li> </ul></div></li> <li class="expanded"><a href="/web/20201114002552/https://www.drupal.org/download" title="Build your solution on Drupal">Build</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/download" title="Download and Extend Drupal">Download & Extend</a></li> <li class="leaf"><a href="https://web.archive.org/web/20201114002552/https://git.drupalcode.org/project/drupal" title="">Browse Repository</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/documentation" title="">Documentation</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/project/modules" title="Find modules to extend Drupal to meet any need">Modules</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/project/themes" title="Browse themes as a starting point for making your Drupal site your own">Themes</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/project/distributions" title="Use a distribution to start with a version of Drupal customized to purpose">Distributions</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/project/issues" title="Dive into the issues queues and contribute back to Drupal">Issue queues</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/about/core" title="">Strategic Initiatives</a></li> </ul></div></li> <li class="expanded"><a href="/web/20201114002552/https://www.drupal.org/industries" title="Examples of solutions built on Drupal">Solutions</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/industries" title="Learn why Drupal is the best solution for your industry">By industry</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/features" title="">By feature</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/case-studies" title="View Drupal success stories">Case studies</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/hosting" title="Find a solution for hosting your Drupal application">For hosting</a></li> </ul></div></li> <li class="expanded"><a href="/web/20201114002552/https://www.drupal.org/drupal-services" title="Buy Drupal Products and Services">Services</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/drupal-services" title="View the Drupal service provider marketplace">Marketplace</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/hosting" title="Find trusted Drupal hosting providers">Hosting</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/training" title="Find expert Drupal training">Training</a></li> </ul></div></li> <li class="expanded"><a href="/web/20201114002552/https://www.drupal.org/community" title="Drupal Community">Community</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/community" title="View the community portal and find all the ways you can contribute to Drupal">Portal</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/organizations" title="Learn about the organizations that are part of the Drupal ecosystem">Organizations</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/forum" title="Find support or chat with the community on the forum">Forum</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/community/agency-marketing/promotedrupal" title="">Promote Drupal</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/case-studies/community" title="">Community Case Studies</a></li> <li class="last leaf"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/swag?utm_source=drupalorg&utm_medium=banner&utm_campaign=drupal_swag_shop_2020_09_17" title="Purchase Drupal merchandise and be the coolest kid on the block">Drupal Swag</a></li> </ul></div></li> <li class="expanded"><a href="/web/20201114002552/https://www.drupal.org/documentation" title="Resources to help you on your Drupal journey">Resources</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/docs/user_guide/en/index.html" title="The Drupal 8 user guide will get you up to speed in no time">User guide</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/documentation" title="Drupal Documentation">Documentation</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/support" title="Support for using Drupal">Support</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/security" title="Find information about security releases for Drupal">Security</a></li> <li class="leaf"><a href="https://web.archive.org/web/20201114002552/https://jobs.drupal.org/" title="Drupal Jobs">Jobs</a></li> <li class="leaf"><a href="https://web.archive.org/web/20201114002552/https://events.drupal.org/" title="Learn about official Drupal Association events">Events</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/subscribe" title="">Newsletter</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/news" title="News about the Drupal ecosystem">Project News</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/association/supporters/press" title="News and press releases from Drupal Association supporting partners">Partner Press</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/about/9" title="Prepare for Drupal 9">Drupal 9</a></li> </ul></div></li> <li class="expanded active-trail"><a href="/web/20201114002552/https://www.drupal.org/association" title="About the Drupal Association - the non-profit that supports the Drupal project" class="active-trail">Give</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/association" title="Learn about the Drupal Association - the nonprofit that supports the Drupal project">Drupal Association</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/association/supporters" title="Learn more about the organizations that support the Drupal Association and our mission">Supporters</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/promotedrupal" title="">Promote Drupal</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/association/support" title="We depend on you to move the Drupal project forward">Join us</a></li> <li class="last leaf active-trail"><a href="/web/20201114002552/https://www.drupal.org/drupalorg" title="" class="active-trail active">About Drupal.org</a></li> </ul></div></li> <li class="expanded"><a href="https://web.archive.org/web/20201114002552/https://events.drupal.org/" title="Find Drupal Events around the world, from the official DrupalCons, to community Camps and Meet-Ups">Events</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="https://web.archive.org/web/20201114002552/https://events.drupal.org/global2020" title="">DrupalCon Global</a></li> <li class="leaf"><a href="https://web.archive.org/web/20201114002552/https://events.drupal.org/europe2020" title="DrupalCon Europe| Dec 8-11, 2020">DrupalCon Europe</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/community/events" title="">Community Events</a></li> <li class="last leaf"><a href="https://web.archive.org/web/20201114002552/https://www.drupical.com/" title="A calendar of Drupal events around the world.">Drupical</a></li> </ul></div></li> <li class="last expanded"><a href="/web/20201114002552/https://www.drupal.org/try-drupal" title="Try Drupal">Try Drupal</a><div class="menu-block"><ul class="menu button"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/try-drupal" title="Demo Drupal online with a Drupal platform partner">Demo online</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/download" title="">Download</a></li> </ul></div></li> </ul></div><a class="close-btn" href="#top">Return to content</a> </div> </div> </div> <div id="block-search-form" class="block block-search"> <div class="block-inner"> <div class="content"> <form action="/web/20201114002552/https://www.drupal.org/drupalorg" method="post" id="search-block-form" accept-charset="UTF-8"><div><div class="container-inline"> <h2 class="element-invisible">Search form</h2> <div class="form-item form-type-textfield form-item-search-block-form"> <label class="element-invisible" for="edit-search-block-form--2">Search </label> <input placeholder="Search…" type="text" id="edit-search-block-form--2" name="search_block_form" value="" size="15" maxlength="128" class="form-text"/> </div> <div class="form-actions form-wrapper" id="edit-actions"><input alt="Search" type="image" id="edit-submit" name="submit" value="Search" src="/web/20201114002552im_/https://www.drupal.org/sites/all/themes/bluecheese/images/icon-w-search.svg" class="form-submit"/></div><input type="hidden" name="form_build_id" value="form-EKAdtgBo9qhAKvicZpJaUp2IlmgNDKIo-f1h56JkwsQ"/> <input type="hidden" name="form_id" value="search_block_form"/> </div> </div></form> </div> </div> </div> <div id="block-system-user-menu" class="block block-system block-menu"> <div class="block-inner"> <div class="content"> <div class="menu-block"><ul class="menu"><li class="button default"><a href="#block-system-user-menu"><img src="https://web.archive.org/web/20201114002552im_/https://www.drupal.org/sites/all/themes/bluecheese/images/icon-w-user.svg" alt="Log in, view profile, and more"></a><ul><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/user/login?destination=node/2580639" title="">Log in</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/user/register?destination=node/2580639" title="">Create account</a></li> </ul></li></ul></div> </div> </div> </div> </div> </nav> </div> <div id="header" class="clearfix"> <div id="header-inner" class="container-12 clearfix"> <div id="header-left"> <div id="site-name"><a href="/web/20201114002552/https://www.drupal.org/" title="Drupal"><img src="https://web.archive.org/web/20201114002552im_/https://www.drupal.org/files/drupal-wordmark.svg" alt="Drupal"/></a></div> </div> <div id="header-right"> </div> </div> </div> <div id="banner"> <div class="region region-banner"> <div id="block-drupalorg-announcements" class="block block-drupalorg"> <div class="block-inner"> <div class="content"> <div class="announcement"><img class="photo" src="https://web.archive.org/web/20201114002552im_/https://www.drupal.org/files/announcements/DCGLO-Icon-100X100.png" alt="Announcement icon" title="Announcement icon"/>DrupalCon Europe has 4 keynotes, 119 sessions and 6 workshops in five tracks included with each ticket. Don’t miss the opportunity to connect with the Drupal community online 8-11 December, 2020.</div> <div class="cta"><a href="https://web.archive.org/web/20201114002552/https://events.drupal.org/europe2020" class="global-announce-banner drupalcon-europe-banner">Visit DrupalCon Europe Website</a></div> </div> </div> </div> </div> </div> <div id="page" class="clearfix"> <div id="page-heading"> <div id="page-title-tools" class="container-12 clearfix" role="navigation"> <div class="page-title-wrapper"> </div> </div>  <div class="breadbox"><nav class="breadcrumb container-12"><span><a href="/web/20201114002552/https://www.drupal.org/">Home</a></span><span><a href="/web/20201114002552/https://www.drupal.org/association" title="About the Drupal Association - the non-profit that supports the Drupal project">Give</a></span></nav></div> <h1 id="page-subtitle" class="container-12">Drupal.org</h1> </div>  <div class="container-12 page-inner"> <div id="main" role="main"> <div id="content" class="clearfix"> <div id="content-inner" class="clearfix"> <div class="region region-content"> <div id="block-system-main" class="block block-system"> <div class="block-inner"> <div class="content"> <div class="panelizer-view-mode node node-full node-section node-2580639"> <div class="panel-display hydra panel-layout clearfix "> <div class="container preface clearfix panel-panel"> <div class="container-inner preface-inner panel-panel-inner"> </div> </div> <div class="container content clearfix"> <div class="container-inner content-inner panel-panel-inner"> <div class="column-content-region top-right-content column panel-panel"> <div class="column-content-region-inner top-right-content-inner column-inner panel-panel-inner"> <div class="panel-pane pane-block pane-og-menu-og-single-menu-block" id="drupalorg"> <h2 class="pane-title"> <a href="/web/20201114002552/https://www.drupal.org/drupalorg" class="active">Drupal.org</a> </h2> <div class="pane-content"> <ul class="menu"><li class="first leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/roadmap" title="">Roadmap</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/style-guide" title="">Style guide</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/personas" title="">User personas</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/docs" title="Drupal.org documentation">Documentation</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/software">Software</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/hardware">Hardware</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/help">Get help</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/change-notifications">Change Notifications</a></li> <li class="leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/blog">Drupal.org blog</a></li> <li class="last leaf"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/contribution-credit">Contribution Credit</a></li> </ul> </div> </div> <div class="panel-separator"></div><div class="panel-pane pane-custom pane-1"> <div class="pane-content"> <p style="padding-top: 1em; border-top: 1px solid gainsboro;">This area of the site provides information about Drupal.org itself and its infrastructure. For information about Drupal, the software, see <a href="/web/20201114002552/https://www.drupal.org/about">About Drupal</a>, <a href="/web/20201114002552/https://www.drupal.org/documentation">Documentation</a>, <a href="/web/20201114002552/https://www.drupal.org/start">Get Started</a>.</p> </div> </div> </div> </div> <div class="column-content-region left-content column panel-panel "> <div class="column-content-region-inner left-content-inner column-inner panel-panel-inner"> <div class="panel-pane pane-entity-field pane-node-body"> <div class="pane-content"> <div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><img src="/web/20201114002552im_/https://www.drupal.org/files/community.png"/><br/><br/><strong>Drupal.org</strong> is a home of the Drupal project and the Drupal community. It is supported and maintained by the <a href="https://web.archive.org/web/20201114002552/http://assoc.drupal.org/" rel="nofollow">Drupal Association</a> with the help of the Drupal community volunteers. Created in 2001, it is one of the largest, continuously operating examples of Drupal.</p> <p>Over the years, Drupal.org has grown from a single server owned by a contributor to multiple racks at the data center, plus cloud resources and content distribution networks spread across the globe. Drupal.org is more than a single site. There are over 20 services and sub-sites that make up the <a href="/web/20201114002552/https://www.drupal.org/ecosystem" rel="nofollow">ecosystem</a> that powers the Drupal community.</p> <p>Follow Drupal.org on Twitter: <a href="https://web.archive.org/web/20201114002552/https://twitter.com/drupal_org" rel="nofollow">news and updates</a>, <a href="https://web.archive.org/web/20201114002552/https://twitter.com/drupal_infra" rel="nofollow">infrastructure announcements</a>, <a href="https://web.archive.org/web/20201114002552/https://twitter.com/drupalorgcommit" rel="nofollow">commits (and deployments)</a>.</p></div></div></div> </div> </div> <div class="panel-separator"></div><div class="panel-pane pane-views-panes pane-blog-panel-pane-2" id="recent-posts"> <h2 class="pane-title"> Recent posts </h2> <div class="pane-content"> <div class="view view-blog view-id-blog view-display-id-panel_pane_2 view-dom-id-314efffc68b45497f6067146f2ae345c"> <div class="view-content"> <div class="views-row views-row-1 views-row-odd views-row-first"> <div class="views-field views-field-title"> <span class="field-content"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/blog/live-deployment-previews-for-drupal-core-thanks-to-tugboatqa">Live deployment previews for Drupal Core (Thanks to TugboatQA!) </a></span> </div> </div> <div class="views-row views-row-2 views-row-even"> <div class="views-field views-field-title"> <span class="field-content"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/blog/whats-new-on-drupalorg-september-2020">What’s new on Drupal.org - September 2020</a></span> </div> </div> <div class="views-row views-row-3 views-row-odd"> <div class="views-field views-field-title"> <span class="field-content"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/blog/whats-new-on-drupalorg-august-2020">What’s new on Drupal.org - August 2020</a></span> </div> </div> <div class="views-row views-row-4 views-row-even"> <div class="views-field views-field-title"> <span class="field-content"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/blog/developer-tools-initiative-part-7-update-on-the-merge-request-beta">Developer Tools Initiative - Part 7: Update on the Merge Request Beta</a></span> </div> </div> <div class="views-row views-row-5 views-row-odd views-row-last"> <div class="views-field views-field-title"> <span class="field-content"><a href="/web/20201114002552/https://www.drupal.org/drupalorg/blog/whats-new-on-drupalorg-special-drupalcon-edition-2020">What's new on Drupal.org? - Special DrupalCon Edition 2020</a></span> </div> </div> </div> </div> </div> </div> </div> </div> <div class="column-content-region bottom-right-content column panel-panel"> <div class="column-content-region-inner bottom-right-content-inner column-inner panel-panel-inner"> </div> </div> </div> </div> <div class="container footer clearfix panel-panel"> <div class="container-inner footer-inner panel-panel-inner"> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div>  </div>  </div> </div>  <div id="footer" role="contentinfo"> <div class="region region-footer"> <div id="block-drupalorg-crosssite-contrib-partners" class="block block-drupalorg-crosssite"> <div class="block-inner"> <div class="content"> <h2> Thank you to these Drupal contributors </h2> <p>Top Drupal contributor <a class="hc" href="https://web.archive.org/web/20201114002552/https://acquia.com/">Acquia</a> would like to thank their partners for their contributions to Drupal.</p> <div class="contrib-partners"> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.thirdandgrove.com/"><img alt="Third and Grove" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/thirdandgrove.png" width="100%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.acromedia.com/"><img alt="Acro Media" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/Acro-Media-Drupal-Commerce-Experts.png" width="90%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.mediacurrent.com/"><img alt="MediaCurrent" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/mc-blue-mediacurrent.png" width="90%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.qed42.com/"><img alt="QED42" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/logo-new.png" width="90%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://us.ciandt.com/"><img alt="CI&T" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/CI%26T%20Logo%20-%20PANTONE.png" width="90%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://ffwagency.com/"><img alt="FFW" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/FFW_Logo-black.png" width="90%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.palantir.net/"><img alt="Palantir.net" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/logo-transparent_0.png" width="120%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.lullabot.com/"><img alt="Lullabot" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/Lullabot_Logo_Vertical-svg.png" width="75%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.fourkitchens.com/"><img alt="Four Kitchens" src="/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/4K-lockup_0.png" width="90%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.phase2technology.com/services/drupal"><img alt="Phase 2" src="https://web.archive.org/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/Phase2_Logo_Black.png" width="95%"/></a> </div> <div class="contrib-partner"> <a href="https://web.archive.org/web/20201114002552/https://www.srijan.net/"><img alt="Srijan" src="https://web.archive.org/web/20201114002552im_/https://www.drupal.org/files/styles/grid-3/public/Neo%20Srijan%20Noir.png" width="95%"/></a> </div> </div> </div> </div> </div> <div id="block-drupalorg-crosssite-drupalorg-footer" class="block block-drupalorg-crosssite"> <div class="block-inner"> <div class="content"> <h4 class="element-invisible">News items</h4><ul class="drupal-news"><li class="0 first"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/news">News</a></li> <li class="1"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/planet" title="News from Drupal community members">Planet Drupal</a></li> <li class="2"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/about/media-kit/social-media" title="Drupal on social media">Social media</a></li> <li class="3"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/subscribe">Sign up for Drupal news</a></li> <li class="4"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/security" title="Announcements from the Drupal Security Team">Security advisories</a></li> <li class="5 last"><a href="https://web.archive.org/web/20201114002552/https://jobs.drupal.org/" title="Drupal Jobs">Jobs</a></li> </ul><h4 class="element-invisible">Our community</h4><ul class="community"><li class="0 first"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/community">Community</a></li> <li class="1"><span><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/drupal-services" title="People and organizations offering Drupal services">Services</a>, <a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/training" title="People and organizations offering Drupal training">Training</a> & <a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/hosting" title="Organizations offering Drupal hosting">Hosting</a></span></li> <li class="2"><a href="https://web.archive.org/web/20201114002552/https://groups.drupal.org/groups" title="groups.drupal.org">Groups & Meetups</a></li> <li class="3"><a href="https://web.archive.org/web/20201114002552/https://events.drupal.org/" title="Upcoming and past DrupalCons">DrupalCon</a></li> <li class="4 last"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/dcoc" title="Drupal code of conduct">Code of conduct</a></li> </ul><h4 class="element-invisible">Documentation</h4><ul class="get-started"><li class="0 first"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/documentation" title="Documentation for working with Drupal">Documentation</a></li> <li class="1"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/docs">Drupal Guide</a></li> <li class="2"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/docs/user_guide/en/index.html">Drupal User Guide</a></li> <li class="3"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/documentation/develop">Developer docs</a></li> <li class="4 last"><a href="https://web.archive.org/web/20201114002552/https://api.drupal.org/" title="Drupal API reference">API.Drupal.org</a></li> </ul><h4 class="element-invisible">Drupal code base</h4><ul class="download-extend"><li class="0 first"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/download">Download & Extend</a></li> <li class="1"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/project/drupal" title="Download the latest version of the Drupal software">Drupal core</a></li> <li class="2"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/project/project_module" title="Download add-on features and functionality">Modules</a></li> <li class="3"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/project/project_theme" title="Download pre-designed styles for Drupal">Themes</a></li> <li class="4 last"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/project/project_distribution" title="Download a pre-packaged Drupal site">Distributions</a></li> </ul><h4 class="element-invisible">Governance of community</h4><ul class="about"><li class="0 first"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/about">About</a></li> <li class="1"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/about/features/accessibility" title="Our committment to accessibility">Web accessibility</a></li> <li class="2"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/association" title="About the Drupal Association">Drupal Association</a></li> <li class="3"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/drupalorg" title="About Drupal.org">About Drupal.org</a></li> <li class="4"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/terms" title="Drupal.org terms of service">Terms of service</a></li> <li class="5 last"><a href="https://web.archive.org/web/20201114002552/https://www.drupal.org/privacy" title="Drupal.org privacy policy">Privacy policy</a></li> </ul> </div> </div> </div> <div id="block-block-77" class="block block-block"> <div class="block-inner"> <div class="content"> <p>Drupal is a <a href="https://web.archive.org/web/20201114002552/http://drupal.com/trademark">registered trademark</a> of <a href="https://web.archive.org/web/20201114002552/https://dri.es/">Dries Buytaert</a>.</p> </div> </div> </div> </div> </div> <div class="region region-page-bottom"> <script type="text/javascript"> (function(){ window._pxAppId = 'PXVnPBBfwe'; window._pxParam2 = ''; window._pxParam3 = '0'; var p = document.getElementsByTagName('script')[0], s = document.createElement('script'); s.async = 1; s.src = '/VnPBBfwe/init.js'; p.parentNode.insertBefore(s,p); }()); </script> <noscript> <div style="position:fixed; top:0; left:0; display:none" width="1" height="1"> <img src="/web/20201114002552im_/https://www.drupal.org/VnPBBfwe/xhr/api/v1/collector/noScript.gif?appId=PXVnPBBfwe"> </div> </noscript> </div> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__B0FBwiP97ZnD38IFraZus4upS4KVkMXI3ou0fJ2ZXGA__pPDESRJz9GHsxqQIwQ_V8xnFYEH5jipG2eicsfrdWCs__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script>    <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__79M6UrZjAw3oNGnUjsWip12JsvnUZmJGA3h9LI0kuzE__LqE6uSZqCOZhJYW910TDw_HTQzBKUPTZxunfaWkalq8__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer" onload="if(jQuery.isFunction(jQuery.holdReady)){jQuery.holdReady(true);}"></script>  <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__pqoYaVR8NVhof-vNXe50j2TKhFv__IihVag_h4G6kus__B4mbn4wICLQjWm1m3-z1kw8F1FtP0cDAHKp00Xy_-88__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__H5AFmq1RrXKsrazzPq_xPQPy4K0wUKqecPjczzRiTgQ__Gnv3ZTafk9EeOiFxo-EtnyI4C4VvBtyZ1MDogxDnRm0__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer" onload=" function advagg_mod_1() { // Count how many times this function is called. advagg_mod_1.count = ++advagg_mod_1.count || 1; try { if (advagg_mod_1.count <= 40) { init_drupal_core_settings(); // Set this to 100 so that this function only runs once. advagg_mod_1.count = 100; } } catch(e) { if (advagg_mod_1.count >= 40) { // Throw the exception if this still fails after running 40 times. throw e; } else { // Try again in 1 ms. window.setTimeout(advagg_mod_1, 1); } } } function advagg_mod_1_check() { if (window.init_drupal_core_settings && window.jQuery && window.Drupal) { advagg_mod_1(); } else { window.setTimeout(advagg_mod_1_check, 1); } } advagg_mod_1_check();"></script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__Oc0wwB7MVRfxtYw6EQM7d9sXj9PAQePoWSzQJ0uTk6c__iXqOGoaPhZHCPEspUr5BC8BwOx5P8B11xv7VOhoUii8__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__FabcJ6qluktliDejymsuV-FqaN_HyMKGe93c2rO9Ky0__el1ZLGkKneOoCS6OWa01WHuIEsTsXZ46MRLCF390Fbw__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__xNXZEl6CREO_N4cX50nXAG3o3PPW1f2SzBBHY8rEKV8__VIWb8OlUCjFhIchzKvf9cz5jnM3cNlwpsZXvC45G1tI__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__ENYUZMe5BHbMK8_pF3i18y1CtuMx_ItPRfjUOF7vUds__MXaxQPtP7z2LRCIe-IOxTRyNSvHNhJSb9SX1jpwq-Z8__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__pLKQd4r7OrHglE7Qkqw53K2UXCqQdhqQ9v0cz7hMCQY__OErfYuQdGbFHcCoLoUW_ESSvaumApNojzjJit8-2xcw__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__hHUWFbMAa11eJtx5V0ym9o0YBsB1udk34qUT5wr1ihI__M46LCs48GV2cgh7lT91U2Ezj_XL8HZW2gMfJdBnqOJw__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript"> <![CDATA[//><!]]> </script> <script type="text/javascript" src="/web/20201114002552js_/https://www.drupal.org/files/advagg_js/js__vj0LjvNwl-3K1P9LGT4BGuXCZcAovYsVlVmoJN3TMRg__KW8SiGceRY3sjIKVrffDjf2MK4A5Vp3EDDxVO-4pegI__YaNGWokqa69Wq8hHbkE322PVJ8I-GmpfBsT8LGsMpcI.js" defer="defer"></script> <script type="text/javascript">window.NREUM||(NREUM={});NREUM.info={"beacon":"bam-cell.nr-data.net","licenseKey":"e671e25255","applicationID":"4266189","transactionName":"Z1AEbREHVxAFU0RRV14aJ1oXD1YNS15fXF1vRQdeBjlPCgFH","queueTime":0,"applicationTime":770,"atts":"SxcHG1kdRB4=","errorBeacon":"bam-cell.nr-data.net","agent":""}</script></body> </html>