created: 20180323092308399
modified: 20180323092547312
tags: Features
title: StartupActions
type: text/vnd.tiddlywiki

During startup, TiddlyWiki executes any ActionWidgets found in tiddlers with the following system tags:

* <<tag "$:/tags/StartupAction">> (executed on all platforms)
* <<tag "$:/tags/StartupAction/Browser">> (only executed when running in the browser)
* <<tag "$:/tags/StartupAction/Node">> (only executed when running under Node.js)

Startup actions are useful for customising TiddlyWiki according to environmental factors such as the screen size. For example, the following action widgets when placed in a tiddler tagged <<tag "$:/tags/StartupAction/Browser">> will cause the sidebar to be hidden by default when the screen width is less than 1000 pixels:

```
<$reveal type="lt" state="$:/info/browser/screen/width" text="3000">
<$action-setfield $tiddler="$:/state/sidebar" $value="no"/>
</$reveal>

<$reveal type="gteq" state="$:/info/browser/screen/width" text="3000">
<$action-setfield $tiddler="$:/state/sidebar" $value="yes"/>
</$reveal>
```

Note that global macros are not available within startup action tiddlers by default. If you need to access them then you'll need to explicitly include them:

```
<$importvariables filter="[[$:/core/ui/PageMacros]] [all[shadows+tiddlers]tag[$:/tags/Macro]!has[draft.of]]">
...actions that depend upon global macros...
</$importvariables>
```