Previously reserved for urgent warnings like trapped or starving status, all warnings (some of which were previously yellow, like breathability and crops) are now red. I can't find anything about this change mentioned in the update post, and it seems to remove functionality so I figured it would be a good idea to report it.
1. Achieve low breathability by having a dupe hang out in non-breathable air for some time
2. Notice the warning is red rather than yellow like it is in main branch