fascinating, seems like scoping behavior is implemented by localizing the hidden stash entry :)

#!perl
use Data::Dumper qw/Dumper/;

open my $fh,"<",'/tmp/tst';
my $outer=$fh;

print 0+($outer == $fh),": ", Dumper $fh;
{
    open my $fh,"<",'/tmp/tst';
    print 0+($outer == $fh),": ", Dumper $fh;
}
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out

1: $VAR1 = \*{'::$fh'};
0: $VAR1 = \*{'::$fh'};
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