Editor is not adopting system theme settings:A11y_Monacoeditor_Theme

[kapilvaishna]

Monaco Editor Playground Link

https://microsoft.github.io/monaco-editor/playground.html?source=v0.55.1#example-creating-the-editor-hello-world

GitHubTags:

#A11yTCS; #A11ySev3; #A11yMAS;#Desktopweb; #Win11; #Visual Studio Code Client; #VisualStudioCode-Web-Apr2021; #ChromiumEdge; #a11y-monacoeditor;#PartnerBug;#WCAG4.3.1;

Environment Details:

#URL: Monaco Editor (microsoft.github.io)
Application name: Monaco Editor
Chromium edge: Version 147.0.3912.86 (Official build) (64-bit)
Windows 11 Enterprise (Version 24H2)  
OS Build 26100.5074

Reproduction Steps

1. Hit the URL: https://microsoft.github.io/monaco-editor/playground.html?source=v0.55.1#example-creating-the-editor-hello-world
2. Monaco editor page will appear.
3. Apply system themes
4. Observe that editor is not adopting the system themea.

Actual Behavior

The editor does not follow the system (OS) theme. Even when the system theme is changed (e.g., Aquatic, Desert), the editor continues using its own previously selected theme.

Expected Behavior

The editor should adopt and reflect the system theme.

User Impact:

Users relying on system-level themes, especially High Contrast or Dark Mode for accessibility, may experience inconsistent visuals, reduced readability, and difficulty using the application effectively.

Attachment

5312_Theme.mp4

[hawkticehurst]

Hi @kapilvaishna this is intentional. We do not adopt system theme colors in Monaco editor. You can see the PR where this change was made, but to summarize: We disabled forced color adjustments in order to adhere to what VS Code desktop does and Monaco editor instead relies on the custom built-in high contrast themes that we ship.