I became frustrated after receiving PPTX files, perhaps roundtripped through Google slides, from a consultant that included strange fonts that caused errors while editing and saving. PowerPoints replace fonts function was no help. So I started to investigate how to solve the problem from the commandline and potentially build scripts to make processing easier.
Most of these one liners require GNU Grep for the extended regex. The grep and egrep included on MacOS do not work. I'm using this version of GNU Grep, aka ggrep:
ggrep (GNU grep) 3.7
Packaged by Homebrew
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