I do it occasionally, usually on books with less than 64 pages. What works for me is to just stick in a tag (something like <PAGE_NUMBER_TAG/> by hand in the code and then run a python script that iterates through the  epub and changes them to sequential page numbers.

But if at all possible prefer to just go back to the InDesign files and redo the epub using Laura’s fantastic pagestaker script.. In most cases it’s actually faster.

a wooden table with a white keyboard on top, and a persons hand writing on a piece of paper

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