Issue #3484966 by mondrake, catch, smustgrave, andypost, alexpott, mstrelan, longwave, bbrala: Allow executing unit tests on multiple PHP images without having to duplicate unit tests across all environment combinations

Issue #3504745 by catch: Move cspell, build, and w3c legacy jobs around to optimise gitlab job order

Issue #3502629 by rkoller: Change the test-only pipeline service from with-chrome to with-selenium-chrome

Issue #3494332 by catch, berdir, longwave, godotislate, oily, rkoller, quietone: Functional Javascript tests are silently skipped on Gitlab CI due to selenium standalone configuration

Issue #3476189 by mondrake, cmlara, fjgarlin, murz, longwave, andypost, larowlan: [CI] Use sudo -E to execute run-tests.sh

Issue #3465602 by catch, quietone, smustgrave: Order tests by number of public methods to optimize gitlab job times

This reverts commit 52dc1d76.

Issue #3463286 by catch: Fix selenium performance/stampede issues in gitlab config and BrowserTestBase

Issue #3463534 by alexpott, catch, longwave: Performance test gitlab job is broken - revert to use chromedriver

Issue #3400366 by mondrake, alexpott, mglaman, longwave, Spokje: Remove DrupalComponentTestListenerTrait and replace with a PHPStan rule

Issue #3109556 by finnsky, nod_, longwave, effulgentsia, Ambient.Impact: Update from Yarn 1 to Yarn 4

Issue #3240792 by justafish, alexpott, andypost, smustgrave, longwave: Use lullabot/mink-selenium2-driver and lullabot/php-webdriver for functional browser testing

Issue #3402061 by fjgarlin, alexpott, smustgrave, catch, longwave: Disable DNS prefetch in Chromedriver on gitlabci

Issue #3401047 by Spokje, longwave, smustgrave, fjgarlin: Nightwatch output on GitLab not easily readable

Issue #3405242 by fjgarlin: GitLab CI pods load too high when running multiple pipelines at the same time