The Plugin details modal custom implementation in the Plugins page conflicts with
other Thickbox instances added by plugins. Thickbox shows its age and has been
modified over time to suit core needs. However, WordPress should do its best to
not create conflicts with the native Thickbox styles and functionalities. Plugin
authors should be able to use `add_thickbox()` in any admin page as documented,
without having to worry about potential errors.
- fixes a JavaScript error when closing a native Thickbox modal in the Plugins page
- avoids to override the native Thickbox modal styles
- uses a CSS class to target the Plugin details modal and remove a pile of overqualified CSS selectors
Fixes#41417.
Built from https://develop.svn.wordpress.org/trunk@41356
git-svn-id: http://core.svn.wordpress.org/trunk@41189 1a063a9b-81f0-0310-95a4-ce76da25c4cd