This PR removes validation of saved bookmarks and system paths in File
Browser. The act of checking validity of a path can result in a timeout
that can last many seconds. Blender will have a very long startup time
if any such items are disconnected, invalid, offline, or removed. Even
if these paths are not used during the Blender session, like network
shares used only at work, web storage for some non-Blender use, a
shortcut to a USB drive, etc. Items will not be greyed out, and
clicking on one will result in a timeout _at that time_ but this seems
like expected behavior.
Pull Request: https://projects.blender.org/blender/blender/pulls/138218