In T322735#8382628, @taavi wrote:

https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar

Everything is good on our side, I can even say that on a non-wmf wiki, the modifications made by the equipped works with :
PHP 8.1
Elasticsearch 7.17.6

Good deduction, the error came from elastica which does not update its dependencies via compose in the main folder.

I added some more information because it seems that this problem comes from php 8.1 (for the search suggestion) and php 8.0 and 8.1 for CirrusSearch itself.
These two concerns were not present until now, we follow the wmf cycles in 8.1 the release of php 8.1.

Hello,
We use mediawiki on two wikis in Wmf21 (and follow the wmf cycle) with PHP 8.1 and elasica, no problem to report since many months.
Sincerely
Kims

In T248925#7661535, @Reedy wrote:

In T248925#7661452, @Falloutgen wrote:

I would say that the problem is related to this task, Elastica does not update its dependencies automatically with compose in the MediaWiki source folder:

https://phabricator.wikimedia.org/T173141

And that's not a PHP 8 specific issue either.

You're welcome, we are also here to try the WMF :)

In T305123#7823198, @Jdlrobson wrote:

Thanks for the report! We're investigating this issue in T303860.

(Also the feature is still in development so I don't recommend using it right now in a production setting!)

I confirm that the bug is solved since the last WMF5 production version.

Hello,
Indeed, I forgot, we display vector 2022 by default.
I just deactivated codemirror by default, but if you want to observe the problem, you can go to our site and activate it in Edit mode from the toolbar:
fallout-wiki.com
We don't see any error in no fail, we don't use any customization though, the only option is the new summary :)
I don't see any problem with the test wiki :/
Sincerely,
Kims

I would say that the problem is related to this task, Elastica does not update its dependencies automatically with compose in the MediaWiki source folder:

I just solved the problem by running directly compose from the extensions/Elastica folder.
The documentation suggested that you should run compose from the mediawiki installation directory.
Everything works :)
Kims

It is indeed an error that appears since the php 8 and 8.1 branch (already reported on the CirrusSearch page).
Everything works without worries on the versions of php 7.3 and 7.4 :)

In T248925#7661046, @Reedy wrote:

In T248925#7659109, @Sosodank wrote:

just wanted to report that i've had my Mediawiki 1.37.1 installation running on Debian Unstable's PHP 8.1.2 for about a week now, and seen zero problems. this has included search, editing, and creating new pages. looking good!

I think most of the more recent fixes are potential logspam (for upcoming deprecations)... Most things should work fine otherwise