Explain undocumented features of startup tiddlers (#3153)

editions/tw5.com/tiddlers/customising/Configuring startup tiddlers.tid

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+created: 20180305174809089
+modified: 20180305175534150
+tags: [[Customise TiddlyWiki]]
+title: Configuring startup tiddlers
+type: text/vnd.tiddlywiki
+
+You can configure ~TiddlyWiki to start up using whatever individual or group of tiddlers you want.
+
+In the control panel under the info tab is an input field labeled "Choose which tiddlers are displayed at startup". You can list whatever tiddlers you want to open at startup. You can also use [[filter expressions|Filter Expression]] to open more than one tiddler.
+
+For instance,
+
+```
+[tag[HelloThere]]
+```
+
+will open all tiddlers tagged as //~HelloThere//. 
+
+You can also use this technique to [[preserve open tiddlers at startup|Preserving open tiddlers at startup]]