Timeline: Highlighted weekend days don't update when you change first day of the week

Hey guys, I’ve been wanting to utilize timelines in my workflow for a while now but I have an issue that makes it very annoying to use:

The highlighted weekend days are always SAT and SUN no matter what first day of the week I set in the region settings.

Funnily, this is not an issue in the calendar view which works as expected.

Is this a known bug and can I expect this to be fixed anytime soon? I imagine many people would benefit from a fix.