Since [1], when editing a cover, if no "bg-X" class was selected (like only selecting a "o_ccX"), the broken "bg-" class was saved. It had no effect but better not accumulate non-existing classes as database values. However, fixing this bug actually reveals code inconsistency... which creates other bugs. Some code were preventing to reset the color class value. All that code apparently became useless since [2] as explained in details at [3]. [1]: https://github.com/odoo/odoo/commit/ad59cbd33e0eaf5c7c77f9e5c0b0435917e2c155 [2]: https://github.com/odoo/odoo/commit/e1632434378fd9b550274c2f40261ad48fb77e6d [3]: https://github.com/odoo/odoo/pull/87206#issuecomment-1088619834 Discovered with task-2792006 closes odoo/odoo#88482 X-original-commit: 35ac2fa584fa7304015a9b44573622cb820d390a Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>