There is a glitch in the moodle.org/plugins prechecker where CSS problems of test files in tests/fixtures are highlighted.

For example, the job https://moodle.org/plugins/theme_boost_union/v4.5-r9/35212?smurf=html#css complains about the broken CSS files tests/fixtures/extscss-invalid.scss which is there by purpose and which also cannot be removed as it is needed for tests.

To my understanding, the prechecker should ignore the tests/ folder and not complain about anything there, even though the file contains CSS syntax or has a .scss suffix.

If you look at the run of the same plugin version in Moodle-Plugin-CI, you can see that the "Grunt" step of Moodle-Plugin-CI does it right and does not complain about this file: https://github.com/moodle-an-hochschulen/moodle-theme_boost_union/actions/runs/13735445465/job/38429140867