I have gone through this years set of posts and "hash-tagged" the subjects with broad categories like "#Bug" or "#New" or "#Files".
The purpose of hashtags in groups.io is to enable filtering. You can view the group via the #hashtags "button" on the LHS, and you can restrict the Search to use them. Let us know if you find them helpful.
Meanwhile If you can remember to be careful about using the octothorpe aka hash -> symbol "#" in the subject/topic line, that will reduce the amount of clean-up needed.