kiwidude: thanks, thanks and thanks
Just being able to identify which epubs have inline font declarations it's a
huge time saver. I can take it from there and edit these epubs in Sigil and remove the inline font declarations.
Right now I'm opening every single epub in Sigil and checking for inline font declarations. When you take into account that this is a 4.000+ epubs library, well...I'd probably have to quit my day time job to be able to finish this quest in my lifetime
Regarding covers: I'd just want to put my 2 cents. More info
here.
Many, many thanks, again.