Cursor misaligned in MR UI
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### Summary
The cursor sporadically becomes misaligned with the page. That is, when you click it doesn't click
on what you were hovering.
### Steps to reproduce
1. Create an MR
2. Navigate to the diff view in Safari
3. Scroll up and down and interact with the file browser
4. Notice that clicking on a file will click on a file a few above in the list
### Example Project
Any project will do this.
### What is the current *bug* behavior?
Clicking is offset by some vertical amount.
### What is the expected *correct* behavior?
Clicking should click the element my cursor is on.
### Relevant logs and/or screenshots
Here is a comparison of the highlight behavior of one of the merge request tabs,
since it's easiest to show statically.


You can see that in the first one my cursor is below the button, but it is highlighted
and the cursor is in "hand mode" indicating it is clickable (and indeed clicking in that position
works). In the second screenshot my cursor is directly on the button but it is not indicated as clickable
and clicking does nothing.
### Output of checks
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This bug happens on GitLab.com
### Possible fixes
Re-sizing the window can sometimes fix it. Re-loading the page seems to sometimes fix
it.
issue