Hmm I think you miss read my post.
Calibre used to take a couple of minutes to start up, until I saw a post about speeding up program starting times, that suggested NOT including formats in the tag browser. (Now it takes about 10 seconds to start up!!)
(I don't use any Column Coloring rules)
The problem I have is the Duplicate's plugin, 2-3 months ago it would take a few seconds to do a search (5-10? seconds maybe a little more? But it was not an excessive length of time)
Bit now it will take 2-3 minutes!! to do the search, and I still have roughly the same number of books in my library.
My theory was maybe the plugin now needs to do (whatever the tag browser was doing with formats) before it can complete the search?
My Antivirus is Norton. I have no clue when it updates.