The problem with s/\s*#.*$//; is that you might start breaking scripts unexpectedly. Given this (contrived but not unlikely) code snippet

my @fred = (1, 2, 3, 4, 5);
my $lastSub = $#fred;
print qq{$lastSub\n};
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running your substitution will result in

my @fred = (1, 2, 3, 4, 5);
my $lastSub = $
print qq{$lastSub\n};
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Perhaps something like

s{(?<!\$)#.*$}{};
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would be better but there may be other syntax where the hash is not the start of a comment that I haven't thought of.

Cheers,

JohnGG

Update: Found another non-comment occurrence of the # character in the colour values in Tk programs, e.g.

-background => #101010,
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so perhaps now

s{(?<!\$)#(?![0-9a-fA-F]{6}).*$}{};
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