I think I’ve found a small UI bug in App Builder.
When a slider is placed inside a tab, the slider extends beyond the tab container and overlaps the tab header (see screenshot attached).
This issue seems to affect sliders only — buttons inside the same tab display correctly.
“Thanks for reporting this. I tested something similar recently and can see how that would be frustrating when building tabbed layouts. Hopefully the team can reproduce it and get it fixed soon.”