[ldolse]

@capnm, I'm sorry, but I've got to admit I have no idea what problem you're trying to solve with your description. The way I'm planning to go forward is that quality check will flag any epubs which don't agree with your Calibre 'page setup' preferences - regardless of whether an @page declaration already exists. Basically quality check will only ignore epubs which don't agree with exactly what's set in your preferences. So if your preferences are all set to zero that means Quality Check would ignore epubs which either don't have any @page, or have an @page where all margins are set to zero. Any epubs which have any non-zero margins set anywhere are ones that would be flagged as needing fixing.

The whole point is that after you 'fix' them Quality check will no longer flag them as needing fixing...

Regarding jackie_w's and capnm's question about why Calibre specifies @page on a flow by flow level vs css, I recall Kovid mentioning in an old thread that this was in case different margins were required for different flows. That said I'm not sure if Calibre is able to follow through with that logic and set separate margins per flow, maybe someone else can comment....