Missing Resource/Elements/File Panel

I upgraded my site to 2.3, did a bunch of work, everything looked and acted well (save for phpThumbOf issue). Logged out and went home. Thought of something so I went back into my site and the resources/elements/file panel is gone. Not hidden. The two column of security and update checks now span the whole page.

What do I do?

Try clearing your browser cache and cookies. Try setting compress_css and compress_js to No (or 0 if you need to do it directly in the database). Check the Policy to make sure the permissions about viewing the Tree are checked.

Were you logged in while running the upgrade? That can do odd things to your session and cookies.