This PR makes editor diff hunk colors configurable from themes, instead
of hardcoded values.
It introduces 6 new optional theme keys:
- `editor.diff_hunk.added.background`
- `editor.diff_hunk.added.hollow_background`
- `editor.diff_hunk.added.hollow_border`
- `editor.diff_hunk.deleted.background`
- `editor.diff_hunk.deleted.hollow_background`
- `editor.diff_hunk.deleted.hollow_border`
When a theme omits these keys, each color falls back to the existing
version-control color with the previous hardcoded opacity values:
- Light defaults:
- background_opacity = 0.16
- hollow_background_opacity = 0.08
- hollow_border_opacity = 0.48
- Dark defaults:
- background_opacity = 0.12
- hollow_background_opacity = 0.06
- hollow_border_opacity = 0.36
There is an existing feature request
https://github.com/zed-industries/zed/discussions/51667
## Screenshots
I used `Modus Themes` (Modus Vivendi) since these themes provide highly
accessible themes.
Original version:
<img width="3248" height="2120" alt="CleanShot 2026-03-17 at 20 26
41@2x"
src="https://github.com/user-attachments/assets/730be802-835d-436e-a1fc-4c60dcb5fce8"
/>
This version:
<img width="3248" height="2120" alt="CleanShot 2026-03-17 at 20 23
09@2x"
src="https://github.com/user-attachments/assets/785c86d3-147e-437f-9624-9576bc201551"
/>
Before you mark this PR as ready for review, make sure that you have:
- [x] Added a solid test coverage and/or screenshots from doing manual
testing
- [x] Done a self-review taking into account security and performance
aspects
- [x] Aligned any UI changes with the [UI
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
Release Notes:
- Added theme keys for configuring editor diff hunk colors.
---------
Co-authored-by: MrSubidubi <finn@zed.dev>
