Added support for dynamic favicons

Now it’s possible to edit $:/favicon.ico with the image editor, and see
the changes instantly reflected in the browser.

core/modules/startup.js

@@ -112,6 +112,21 @@ exports.startup = function() {
 		$tw.rootWidget.addEventListener("tw-clear-password",function(event) {
 			$tw.crypto.setPassword(null);
 		});
+		// Set up the favicon
+		var faviconTitle = "$:/favicon.ico",
+			faviconLink = document.getElementById("faviconLink"),
+			setFavicon = function() {
+				var tiddler = $tw.wiki.getTiddler(faviconTitle);
+				if(tiddler) {
+					faviconLink.setAttribute("href","data:" + tiddler.fields.type + ";base64," + tiddler.fields.text);
+				}
+			};
+		setFavicon();
+		$tw.wiki.addEventListener("change",function(changes) {
+			if($tw.utils.hop(changes,faviconTitle)) {
+				setFavicon();
+			}
+		});
 		// Set up the styles
 		var styleTemplateTitle = "$:/core/ui/PageStylesheet",
 			styleParser = $tw.wiki.parseTiddler(styleTemplateTitle);

core/templates/tiddlywiki5.html.tid

@@ -14,7 +14,7 @@ title: $:/core/templates/tiddlywiki5.html
 <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent" />
 <meta name="format-detection" content="telephone=no" />
 <meta name="copyright" content="{{$:/core/copyright.txt}}" />
-<link rel="shortcut icon" href="favicon.ico">
+<link id="faviconLink" rel="shortcut icon" href="favicon.ico">
 <title>{{$:/core/wiki/title}}</title>
 <!--~~ This is a Tiddlywiki file. The points of interest in the file are marked with this pattern ~~-->
 

editions/tw5.com/tiddlers/Release 5.0.5beta.tid

@@ -8,7 +8,7 @@ type: text/vnd.tiddlywiki
 
 !! Improvements
 
-* 
+* Added support for [[Setting a favicon]]
 
 !! Bug Fixes
 

editions/tw5.com/tiddlers/howtos/Setting a favicon.tid

@@ -0,0 +1,17 @@
+created: 20131224074240979
+modified: 20131224075348329
+tags: howto
+title: Setting a favicon
+type: text/vnd.tiddlywiki
+
+"favicons" are small icons that most browsers display to help users identify websites.
+
+! favicons in the Browser
+
+When TiddlyWiki starts up in the browser it looks for a tiddler called [[$:/favicon.ico]] and dynamically uses it as the favicon for the page. If you modify the image then the favicon changes instantly to reflect it.
+
+! favicons on the Server
+
+On the server, the ServerCommand will serve the tiddler [[$:/favicon.ico]] at the path `/favicon.ico`.
+
+