Tags are being automatically added to posts causing an error

This just started happening today, never had it happen before.

Started a thread about a build of Götzenburg Castle Möckmühl . Added a few attachments of pictures and tried previewing. Got a message about the number of tags allowed being exceeded. Noticed in the Tags area that some tags had been added, but not by me. Deleted those tags and was able to preview the post. Did some editing and clicked Submit New Thread. Received that error message again and sure enough those tags were back in the Tags area. Deleted them again and was able to post the new thread.

Is there something somewhere to disable the automatic inclusion of tags in the Tags area or are the gremlins at it again?:)

Note: Just noticed before submiting this thread that the Tags area was filled in again. Tried the Submit New Thread button and received that error message about "The number of tags you tried to add to this thread exceeded the maximum number of tags by 20." Manually deleted them and the new thread was able to be posted. Those tags seem to show up automatically each time after Preview Post is clicked.