Change 604459 had a related patch set uploaded (by Vidhi-Mody; owner: Vidhi-Mody):
[mediawiki/extensions/Wikibase@master] Selenium: Update to WebdriverIO v6

https://gerrit.wikimedia.org/r/604459

Unable to set up Wikibase locally
https://phabricator.wikimedia.org/P11490

• Add wfLoadExtension( 'Wikibase' ); to LocalSettings.php

Wikibase Installation is unfortunately a bit more complicated than that.

In T255045#6223610, @Lucas_Werkmeister_WMDE wrote:

Wikibase Installation is unfortunately a bit more complicated than that.

Thanks @LucasWerkmeister, that's exactly what we were looking for.

@LucasWerkmeister according to the README.md, mediawiki-vagrant is the recommended local development environment for running selenium tests for wikibase.

I've tried running the tests (master branch), but they are failing with badvalue: Unrecognized value for parameter "action": wbeditentity. See P11609.

Hm, I suspect that README is outdated :/ I believe a lot of Wikibase developers use some version of @Addshore’s mediawiki-docker-dev, but I don’t know a lot about the details because I can’t use Docker on my own laptop (due to cgroups v2).

But that error, and also the “no such special page” errors earlier, sound like Wikibase isn’t installed in that environment for some reason. Maybe this “wikidata” vagrant role is broken?

(For what it’s worth, we’re working on a more standard development environment that we can point other people to, but I think that work isn’t completed yet.)

(And the way I run the browser tests myself is to have a MediaWiki+Wikibase install directly on localhost via Apache2, and point the browser tests at that with something like MW_SERVER=http://localhost MW_SCRIPT_PATH=/wiki1 MEDIAWIKI_USER='Lucas Werkmeister' MEDIAWIKI_PASSWORD='...' npm run selenium-test. Chromedriver runs as a systemd user unit, though the way you’re running it in that paste should work just as well.)

In T255045#6241022, @Lucas_Werkmeister_WMDE wrote:

Hm, I suspect that README is outdated :/

The remark on mediawiki vagrant must have indeed been outdated (or copy pasta from somewhere?), I wonder if it ever worked.
I've submitted https://gerrit.wikimedia.org/r/#/c/mediawiki/extensions/Wikibase/+/607115 to remove this misleading information.

Created dedicated T265149: Upgrade WebdriverIO in Wikidata Bridge as this is its own beast.

Change 604459 merged by jenkins-bot:
[mediawiki/extensions/Wikibase@master] Selenium: Update to WebdriverIO v6

https://gerrit.wikimedia.org/r/604459

Meh - forgot that this is also a parent task.
I guess T256114: Create MediaWiki-Docker/Wikibase & T257520: Error in setting up Wikibase locally can be closed - they were merely bugs on the way to setting wikibase up in order to do the upgrade.
I'll move T265149: Upgrade WebdriverIO in Wikidata Bridge to become its own task under T247844: Upgrade WebdriverIO to v6 in all repositories - it may not be its own repo, but it is its own package.