Fixed-width Issue and MR pages don't interact well with "Layout width" Fixed/Fluid user preference
When the "Layout width" option on https://gitlab.com/profile/preferences is set to "Fluid", the issue and MR description doesn't change to fixed, but the discussion/diffs do:
Issue description is fixed, but discussion is fluid
MR description is fixed, but diffs are fluid
I think that description fixed-ness should follow the user's "Layout width" setting, like the rest of the app.