GLOB and "global" are two different things. You can easily freeze global variables, but you can't freeze typeglobs, see "Typeglobs and Filehandles" in perldata.

use Storable;
bless our $x = [], 'My::class';
print Storable::freeze($x);         # No error, $x is global.

bless my $y = \*STDERR, 'My::class';
print Storable::freeze($y);         # Can't store GLOB items, $y is le
+xical.
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