https://github.blog/changelog/2019-03-18-sticky-file-headers-in-pull-requests/

Looks like they're using the class .sticky-file-header to mark these up so you'll need to adjust some of the selectors to be .file-header:not(.sticky-file-header).

As seen above, the z-index needs changing, and less obvious but more crucial, is that the items in the dropdown list become unclickable.

The header is one part too far down. (If i disable this theme, it works fine)

Other themes i use for GitHub: (All from this Orga)

• Browser: Firefox Developer 77b9 (64-bit)
• Operating System: Windows 10
• Link to page with the issue: https://github.com/StylishThemes/GitHub-FixedHeader/issues (Desktop and Mobile)
• Screenshot:
  
  

On the second its hard to see.

Now that .Header-old is being used the rules need to be updated to include it.

• Browser: FF 72.0.2
• Operating System: Win10-1909
• Link to page with the issue: 9d6a63d
• Screenshot:
  

1. Minimize the code display by clicking the dropdown arrows on the left
2. Click the three dots on the right

#files .file-header { position: sticky !important; } seems to be the culprit.

I used dark style to show it better (unrelated to the problem).

OctoTree overruns the header if expanded with Fixed-Header

• Browser: Chrome 73.0.3683.75
• Operating System: Windows 10 1809 17763.379
• Link to page with the issue: microsoft/vscode@10c0126
• Screenshot:

The header has starting overlapping code changes when opening links.
https://github.com/casz/fastlane/blob/9b7ebab16ebbace1178fc6f6d1f1b232372e5419/fastlane/lib/fastlane/actions/set_info_plist_map.rb#L12-L15

With fixed header on

With fixed header off

Don't recall it being a issue, hence this issue was created.

• Browser:Chrome
• Operating System:MacOS
• Link to page with the issue:none
• Screenshot:

add higher z-indexmay work to this

.Popover {
  z-index: 1001!important;
}

When the mouse isn't pointing at header area, fold the header up but display it again with mouse hover.
You may add an option to define the delay (I suggest 150ms~250ms) to display the header as mouse hover before someone installs this style from USO.

• Browser: FireFox
• Operating System: Windows
• Link to page with the issue: #11
• Screenshot:
  

in PR files changed page,code diff layout may display error when the PR title fixed

• Browser:Chrome
• Operating System:Macos
• Link to page with the issue:https://github.com/StylishThemes/GitHub-FixedHeader/pull/13/files
• Screenshot:
  

Using Refined Github and Dark Theme, I get the following on unified.

The header overlaps the sticky sidebar.

I can't think of an optimal solution... if you add the following css, it doesn't overlap but it jumps down and end up overlapping the page footer in some cases (when using ZenHub which adds extra sections to the sidebar).

.discussion-sidebar.is-stuck {
  margin-top: 50px !important;
}