2f1f0abc6b of core (https://git.wikimedia.org/commit/mediawiki%2Fcore.git/2f1f0abc6b) added a jQuery Cycle file. That is referenced directly in UnitTest (https://git.wikimedia.org/blob/mediawiki%2Fextensions%2FUnitTest/8dc69c6f2cbc6c1cac91558281c0652e6c9984e5/ExtensionsSeleniumSlideshowTemplate.php) (not using ResourceLoader).
There is no ResourceLoader module for jQuery Cycle in core, nor any reference to it (even when it was first added).
We're removing jQuery Cycle in core in https://gerrit.wikimedia.org/r/#/c/138108/ , so this is to flag the issue for anyone who resumes work on UnitTest.
(There does not seem to be a Bugzilla extension for UnitTest)
Version: master
Severity: normal
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=66292