I noticed that after the update all inline sources are showing again. The Settings > Interface > Editor Interface > Hide Inline Sources option seems to be gone (at least I’m unable to find it).
I’m currently using custom CSS by @TaQuangKhoi from this comment
Trouble with 1.6.0 new source display (Hide Inline Sources) - #5 by TaQuangKhoi - thank you for this!
But the option to have the source showing when clicking on a rem that’s nested within another one is super handy - to quickly see the ‘reference’ when I need to know where the info is from, but not overcrowd my whole document. Please bring back this function.