Fix merge request fluid layout gap

Stanislav Lashmanovrequested to merge
slashmanov/fix-mr-fluid-layout-gap into master

What does this MR do and why?

Fixes #479448 (closed).

This MR fixes merge request fluid layout gap. It switches to a fixed value for the gap instead of a percentage one.

Screenshots or screen recordings

Before After
Screen_Recording_2025-06-20_at_04.48.19 Screen_Recording_2025-06-20_at_04.47.40

How to set up and validate locally

  1. Select 'Fluid' layout in your user prefernces
  2. Open any merge request
  3. Scale down browser viewport to 50%
  4. Resize browser window
  5. Observe the gap between sidebar and content to stay the same size

Merge request reports