Originally Posted by Mrs_Often
Thanks for all the replies.
I'm not completely sure but I don't think epub chapters get loaded into cache so that should also help. Testing now.
I had an epub that I couldn't read at all because the chapter was too long 'on the road' - scroll version by Jack Kerouac. If it could have loaded part of it into the cache I reckon it would have. Had to fix it by opening it in Sigil and adding lots of chapter breaks.