fix(DuoChat): Fix pre code color inheritence in dark mode

Scott de Jongerequested to merge
sdejonge-bugfix-safari-dark-mode-pre into main

What does this MR do?

Use inherit instead of initial in pre code blocks in Duo chat messages. This resolves a bug where Safari user-agent stylesheet sets an explict color for code blocks which initial inherits, this makes code text without highlight styles (default content) display as dark (#000000) in dark mode. Using inherit ensures text color is inherited from parent node styles which should be text.color.default.

Recreation steps

  1. Only applies to Safari (I believe but this will update inheritance for all browsers)
  2. Prompt Duo AI for a code snippet e.g. "Can you provide me with a basic "hello world" console.log snippet in JavaScript"
  3. Have dark mode applied in GitLab
  4. Inspect <pre><code> element in chat
  5. Color should be inherit !important to apply same text color as parent node

Screenshots or screen recordings

Before After
CleanShot_2025-11-26_at_11.29.58_2x CleanShot_2025-11-26_at_11.31.07_2x
CleanShot_2025-11-26_at_11.31.48_2x CleanShot_2025-11-26_at_11.32.14_2x

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Accessibility

If this MR adds or modifies a component, take a few moments to review the following:

  • All actions and functionality can be done with a keyboard.
  • Links, buttons, and controls have a visible focus state.
  • All content is presented in text or with a text equivalent. For example, alt text for SVG, or aria-label for icons that have meaning or perform actions.
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