[masterpiga]

Summary

With the mask panel on the canvas, its 1px edge strips were shown and hidden with module focus. They are columns beside the canvas, so every focus change resized the canvas and moved the image by a pixel.

The strips now keep their room while the darkroom uses the canvas position, whatever is focused. With no panel to show they paint the canvas margin color and ignore input.

Screen.Recording.2026-10-17.at.18.31.18.mp4

Referenced issue

Fixes #22651

Checklist

• I have read CONTRIBUTING.md and the coding style.
• I have not merged master into the topic branch.
• The pull request is one logical change, and every commit compiles on its own.
• I ran the relevant tests: unit tests, src/tests/integration/ where the pixelpipe is touched, or darktable-cli as a headless smoke test.
• New user-visible strings use _(), new preferences are registered in data/darktableconfig.xml.in.
• A RELEASE_NOTES.md entry was added (only needed if fixing an issue in a release). Do not reference GitHub issues.

Test instructions

1. Dock mask panel on canvas
2. Focus/unfocus a mask-capable module (e.g., exposure)
3. The canvas should not shift by 1px every time

AI assistance

Co-authored with Claude.

[TurboGit]

Works for me, thanks!

A question, I don't remember having seen that when testing the flexi panel since some weeks... Is there a recent change that could explain that or was I blind ? :)

[masterpiga]

Works for me, thanks!

A question, I don't remember having seen that when testing the flexi panel since some weeks... Is there a recent change that could explain that or was I blind ? :)

Not something that I changed on purpose. I think it's always been there, it's just that one notices only after un-focusing a module. If you jump between modules that can be masked nothing shifts.