Running doom upgrade causes the following error under the 'updating packages' step:
In repository "persp-mode.el", HEAD (on branch "remove-byte-compile") is ahead of branch "master"
No amount of asking the tool to fast-forward resolves the issue

Not sure what's the cause of this, but its solvable by
rm -rf .emacs.d/.local/straight/{repos,build}/persp-mode.el
The solution proposed by @ymarco fixed it for me!
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Not sure what's the cause of this, but its solvable by