I'm compiling Emacs master right now (on macOS Catalina) and have
detected a couple of warnings 'assignment to free variable
repeat-map' (one in tab-bar.el and one in window.el) Which I haven't
seen before...
I don't see any warnings, so please show the warnings you see.
I see them (and have seen them for a week or two), too:
In toplevel form:
tab-bar.el:2093:33: Warning: assignment to free variable ‘repeat-map’
In toplevel form:
window.el:10261:33: Warning: assignment to free variable ‘repeat-map’