Subject: 30.0.50; erc-server-prevent-duplicates uses list instead of repeat

From: Mauro Aranda <[email-masked]>
Date: Tue, 10 Oct 2023 20:19:25 -0300

The docstring of erc-server-prevent-duplicates says it can be either nil
or a list of strings (multiple strings).  So it looks like
:type '(choice (const nil) (list string))
is not right.

It should be:
:type '(repeat string)