This patch improves the popover triangle position by allowing the arrow to be drawn directly at the rounded corner.
This helps with an edge case, where the arrow of the properties panel’s settings popover isn’t drawn under the button but next to it, because it can’t be positioned closer to the popover’s edge.
**Limitations**
While this patch helps with this corner case happening with the default theme, similar situations can still occur when the button that’s emitting the popover is partially off-screen or the theme uses a large //roundness// for the menu back.