When you add custom CSS on an element at the ID level, a CSS icon displays in the structure panel to let users know that element has custom CSS.
When you add custom CSS on an element at the class level, no indicator appears. This is a big bug for teams and design sets, as users can’t easily see that custom CSS has been used on an element.
I feel it’s related so I’ll add on this - you also can’t see there is custom css if you go to a lower breakpoint.
This is actually a cool feature since you can change custom css per breakpoint.
But not knowing Custom CSS is added on a higher breakpoint (not even an indicator in the panel - same as with the borders) makes it really hard to keep track. For those working in teams - nearly impossible to spot.