[ownedbycats]

I ended up using SQLiteStudio to make a dump of my database so that I could use Notepad++ to search for the column name. (Except Notepad++ didn't like the size of it, so I ended up using EmEditor instead.)

I'd left a #read in a saved search used in one of my virtual libraries. And from there a composite column checking virtual_libraries(). Oh, and a column icon checking the virtual library column. That would probably do it. I changed it and the lag's gone.