edit_published_posts capability is broken

[shlomi.tur]

Hi everyone,
After couple of days of debugging, I've just installed WordPress 5.2.1 and found that Contributors can edit their own posts after publishing by Editor.
Moreover, I've tried to turn off the capability manually by using the 'remove_cap' method, but there's no change.

This capability's default should be off as you can see here:
​https://wordpress.org/support/article/roles-and-capabilities/#edit_published_posts

[johnbillion]

Thanks for the report, @shlomitur. As you've observed, contributors cannot edit their own published posts as they are not granted the edit_published_pages capability. The problem you're seeing must be local to your particular installation of WordPress.

I would recommend deactivating the plugins on your site one by one to see if one of them is overriding that capability. Also note that it is possible that a plugin granted that capability to an individual user with the Contributor role, or granted that capability to the Contributor role directly, in which case that capability might still be attached as they get stored persistently in the database.

Failing that, you can install a role and capability management plugin such as ​Members which will allow you to fix the capability.