Required for T364268, T324685 and T363704.
[x] [[ https://www.mediawiki.org/wiki/Selenium/Getting_Started/Create_a_simple_test | Selenium/Getting Started/Create a simple test ]] - [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/345378 | 345378 ]], [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/1055925 | 1055925 ]]
[x] [[ https://www.mediawiki.org/wiki/Selenium/How-to/Create_the_first_test_in_a_repository | Selenium/How-to/Create the first test in a repository ]] - [[ https://gerrit.wikimedia.org/r/c/mediawiki/extensions/examples/+/674939 | 674939 ]], [[ https://gerrit.wikimedia.org/r/c/mediawiki/extensions/examples/+/1064401 | 1064401 ]]
[x] [[ https://www.mediawiki.org/wiki/Selenium/How-to/Debug_with_logLevel | Selenium/How-to/Debug with logLevel ]] - [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/676397 | 676397 ]]
[x] [[ https://www.mediawiki.org/wiki/Selenium/How-to/Debug_with_Visual_Studio_Code | Selenium/How-to/Debug with Visual Studio Code ]] - [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/866436 | 866436 ]], [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/1055406 | 1055406 ]]
[x] [[ https://www.mediawiki.org/wiki/Selenium/How-to/Use_MediaWiki_API | Selenium/How-to/Use MediaWiki API ]] - [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/675813 | 675813 ]], ([[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/680336 | 680336 ]] was causing the tests to fail)
[] [[ https://www.mediawiki.org/wiki/Selenium/Explanation/Page_object_pattern | Selenium/Explanation/Page object pattern ]] - [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/702327 | 702327 ]], [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/702341 | 702341 ]], [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/1064713 | 1064713 ]]
[] [[ https://www.mediawiki.org/wiki/Selenium/Explanation/Stack | Selenium/Explanation/Stack ]] - [[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/675850 | 675850 ]]
[[ https://gerrit.wikimedia.org/r/c/mediawiki/core/+/721790 | 721790 ]] runs core selenium tests 100 times in a row in our CI to test if a newly introduced test is flaky.