Not explicitly written in checklist ( as far as I remember ) but I did submit all the pages of passport where stamps / visa are there, in short non blank pages of PA's passport just to corroborate with what I mentioned in IMM5562. doesn't hurt
What I did was scan all the pages, put the main bio pages first and then the visa/stamps. and uploaded where it asks to upload travel document. Uploaded it as :
PA'S LASTNAME - PA'S FIRSTNAME - TRAVEL DOCUMENT.pdf
HOPE THIS HELPS