title: $:/changenotes/5.4.0/#9641
description: Background actions and media query tracking
tags: $:/tags/ChangeNote
release: 5.4.0
change-type: enhancement
change-category: hackability
github-links: https://github.com/TiddlyWiki/TiddlyWiki5/pull/9641
github-contributors: Jermolene

Introduces [[Background Actions]] that are triggered whenever there is a change to the results of a specified filter.

Building on that, it also introduces a new [[Media Query Tracker Mechanism]] that can track the results of any CSS media query (not just dark mode), storing the results in a shadow `$:/info/...` tiddler

These improvements were cherrypicked from [[#8702 - Colour Handling Improvements|https://github.com/TiddlyWiki/TiddlyWiki5/pull/8702]] when it was deferred until v5.5.0.
