> Note that the path separator are different, for 12.1.1, it is ":", for
> 11.91.0, it is ";". I'm not sure whether it is important.
It surely is, given that ":" is to be intended as a normal character for a path
(see the ":" right after "d").
But I have the same AUCTeX version as you, and it's inserting ";". I have
Windows 7, though. I don't know the mechanism by which AUCTeX changes this
environment variable... could it be that it's customized to the Windows version?
As far as I can see your init customization shouldn't trouble this environment
variable, but I may be mistaken.
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