Seen in this experimental PHP 8.4 build for Wikibase (alongside plenty of errors related to T376711):
2) WikibaseQuality\ConstraintReport\Tests\Checker\RangeChecker\DiffWithinRangeCheckerTest::testDiffWithinRangeConstraintWithinRange fgetcsv(): the $escape parameter must be provided as its default value will change /workspace/src/extensions/Wikibase/lib/includes/Units/CSVUnitStorage.php:42 /workspace/src/extensions/Wikibase/lib/includes/Units/BaseUnitStorage.php:33 /workspace/src/extensions/Wikibase/lib/includes/Units/BaseUnitStorage.php:47 /workspace/src/extensions/Wikibase/lib/includes/Units/UnitConverter.php:67 /workspace/src/extensions/WikibaseQualityConstraints/src/ConstraintCheck/Helper/RangeCheckerHelper.php:66 /workspace/src/extensions/WikibaseQualityConstraints/src/ConstraintCheck/Helper/RangeCheckerHelper.php:110 /workspace/src/extensions/WikibaseQualityConstraints/src/ConstraintCheck/Checker/DiffWithinRangeChecker.php:152 /workspace/src/extensions/WikibaseQualityConstraints/tests/phpunit/Checker/RangeChecker/DiffWithinRangeCheckerTest.php:172
(The test is in WBQC but the affected code is pure Wikibase and I’m pretty sure it’s reachable within Wikibase too.) Should hopefully be a simple fix; compare also T378302.