As posted above, this plugin has been broken for PDF scanning due to a change made in calibre 0.8.53. So users have either had to stick to earlier versions, or learn not to extract from PDFs
.
Attached is my next intended version which
requires calibre 0.8.54 - it would be appreciated if someone could give it a quick whirl before I officially release it.
I believe there is still a very slim chance in exceptional circumstances that scanning a PDF could still cause a calibre crash. I haven't had this happen, but in theory it could do. However when the next calibre 0.8.55 is available some code I have already included in this plugin version will automatically become active and safely handle that situation without crashing. I didn't want users to be stuck waiting for another week for the sake of something they probably won't have happen.
Please can one or two of you try this and let me know on the thread if any issues, then I will officially release it.