`wait-for-build` is completely missing #4647

I think this is caused by the merge box being lazy-loaded, causing the feature to always be disabled by its own exclude condition, since the elements are missing:

https://github.com/sindresorhus/refined-github/blob/ac8de6bd0ef0a6016732a69556e4eb9c014cfd38/source/features/wait-for-build.tsx#L105-L108

Should this check be moved to the init()?
This is also probably affecting some of the other features dealing with the merge box, so maybe making a helper would be useful (e.g. waitForMergeBox() or something)

If we can detect the ability to merge from other parts of the page, that would be enough as an exclude. After that we can just use a regular selector-observer.

By "ability to merge" I mean "exclude non-collaborators", just as a general filter for users who will definitely not need the feature on the page.

It's possible that this is Safari-only since I'm seeing it today in Chrome 🤨

<img width="931" alt="Screen Shot 18" src="https://user-images.githubusercontent.com/1402241/130341926-6230d3a7-e8a8-46eb-a0c3-1aa8240ee2b2.png">

It's possible that this is Safari-only since I'm seeing it today in Chrome

I saw it too on Firefox. Changing the exclude to

() => !select.exists('[aria-label="Edit Pull Request title"]')

fixes it for the most part, but there's also the problem of the build status of the commits being lazy-loaded. Sadly I don't have time to open a PR right now.

I observed this issue on Chrome as well.

I am missing it on Chrome as well.