If I manually create a css and js folder, Drupal deletes them, so I know it is able to access the files directory.
Yes, this.
I notice that jQuery is included, but not until after the homepage slider code tries to call it. It's the very next line, but too late.
Yes, it stopped working as soon as I logged in.
It is also not a very helpful answer to tell people to disable another module, aside from as a temporary workaround. I am sure most people would rather disable Tara than disable Admin Toolbar Extra Tools, which is years older and far more popular. There are plenty of other good themes out there, but only one Admin Toolbar Extra Tools.
It's also a bit annoying to see bug reports closed for a reason that doesn't seem very relevant. It's one thing to leave it open and say "I don't have time to work on this", but quite another to close as "outdated" when there is nothing outdated about the issue, since it appears to be still happening in the latest version.
I'm going to agree with Jelle_S. Any version that breaks backward compatibility should not be a minor version update, it should be a new major version. The failure to do so is the cause of this problem. It is not Drupal's fault, or anything that should be patched around, it's simply that the release was misnamed from the beginning, and is still misnamed.
matthewv789 → created an issue.