Also, I'm a little bit wary of all of the @require-mysql statements because it means we're skipping the tests for SQLite. I don't think it necessarily blocks this, but we might want to track it in some way.

Another potential way to solve this: create a custom Matrix for the SQLite tests, and only run SQLite for WordPress 6.0 and higher. I think this would be my recommended approach.

Another potential way to solve this: create a custom Matrix for the SQLite tests, and only run SQLite for WordPress 6.0 and higher.

This is already the case, actually. What's happening here is that some individual scenarios downgrade to WordPress 4.0 and then upgrade to the latest version.

Can we make sure there are GitHub issues open for the TODO comments? They will probably be forgotten otherwise.

Totally. The only TODO that doesn't have one yet is the one about CUSTOM_USER_TABLE. I'm not yet sure whether it's an issue with the command or the SQLite plugin.

@danielbachhuber WDYT about the reworded comments?