Works for me locally, showing "studenoga".

On hrwiki, the page MediaWiki:November-gen exists with "studeni" and the local overwrite is used

All gen messages exists, please check if the pages contains the correct form of the month name:

• https://hr.wikipedia.org/wiki/MediaWiki:January-gen
• https://hr.wikipedia.org/wiki/MediaWiki:February-gen
• https://hr.wikipedia.org/wiki/MediaWiki:March-gen
• https://hr.wikipedia.org/wiki/MediaWiki:April-gen
• https://hr.wikipedia.org/wiki/MediaWiki:May-gen
• https://hr.wikipedia.org/wiki/MediaWiki:June-gen
• https://hr.wikipedia.org/wiki/MediaWiki:July-gen
• https://hr.wikipedia.org/wiki/MediaWiki:August-gen
• https://hr.wikipedia.org/wiki/MediaWiki:September-gen
• https://hr.wikipedia.org/wiki/MediaWiki:October-gen
• https://hr.wikipedia.org/wiki/MediaWiki:November-gen
• https://hr.wikipedia.org/wiki/MediaWiki:December-gen

Also exists, but with same content as translatewiki.net (waiting for deployed of b371b0623e213e2daa65ab10fd9d97de07b317e5)

• https://hr.wikipedia.org/wiki/MediaWiki:August
• https://hr.wikipedia.org/wiki/MediaWiki:September

@Umherirrender : oh, what a mess. I have no idea why they did that. The local Month-gen messages were in the nominative case. I've deleted them.

I created the local MediaWiki:August and MediaWiki:September messages with the month names in the genitive case so our signatures (~~~~) would work. You can see that they differ in these two edits here (genitive:kolovozA).

MediaWiki:Month is also what's shown in revision lists (recent changes, page history etc.), we'd want that to be MediaWiki:Month-gen

So the question here is: what exactly formats the dates in ~~~~'s and edit revision lists?

PS
Ukrainian Wikipedia page history uses the genitive form for August (N:серпень, G:серпня), but the same page with uselang=hr uses the Croatian month name in the nominative case (N:kolovoz, G:kolovoza).

The $dateFormats in languages/messages/MessagesHr.php needs to use xg instead of F, at least it is used in MessagesUk.php.

gerritbot is asleep... I made a patch: https://gerrit.wikimedia.org/r/c/mediawiki/core/+/1069116

@Ivi104: Gerritbot is not asleep. The commit message format is wrong.

Change #1069116 had a related patch set uploaded (by Aklapper; author: Ivi104):

[mediawiki/core@master] #time should use Month-gen messages in Croatian

https://gerrit.wikimedia.org/r/1069116

@Aklapper: Thank you for the correction!

The two patches should fix all the problems. How soon can we have this? It only affects hrwiki, and I hope it can be treated with some urgency (some of our automatic templates are failing).
Thanks all!

@Aklapper The patch has been live for more than two weeks now with no complaints. What are the next steps for deploying this change into production? As @Ponor has stated above, it is a matter of some urgency. Thank you!

Hi, it has not been live (deployed) but available in Gerrit. :) See https://www.mediawiki.org/wiki/Gerrit/Code_review/Getting_reviews

Adding a note here, as I am discussing the patches at Discord. We're removing mdy and ymd because they are not valid date formats in Croatian. For example: Studeni 28. 2024. and 2024. studeni 28. make no sense in Croatian.

Change #1069116 merged by jenkins-bot:

[mediawiki/core@master] #time should use Month-gen messages in Croatian

https://gerrit.wikimedia.org/r/1069116