[Linux/Wayland] Toolbar box fails to render group list when outside browser window

[GrabbenD]

Describe the bug

Toolbar window does not render the list of groups if the box is drawn outside of browser's window.

Despite the contents not being visible, you can still change tab groups by clicking in the empty box.

To Reproduce

For instance, when the browser is snapped to the right side of the screen and STG toolbar is pinned to the left side, you'll risk drawing the box outside of browser's window if there's another application snapped to the left, like in this screenshot:

If Firefox occupies the entire screen, or is positioned at screen's edge, the box is forced to be drawn inside Firefox's window which successfully renders the list. Example:

Expected behavior

Short term solution could be to force the toolbar box to be drawn inside of browser's confinements/window without overflowing, possibly as an option.

Desktop

• OS: Arch Linux (Wayland/Sway 1.10]
• Firefox version: 131.0.3
• Simple Tab Groups version: 5.2

Additional context

Considering it's possible to interact with the box but not see its contents, could this be caused by wrong z-index?

Workaround

Pin the toolbar to the right side, where it will never overflow the window (since the box is currently always rendered to the left). I personally really enjoy keeping STG Overview Tab pinned (to show it in every group) and sadly this approach keeps it far away from the overview tab.

[GrabbenD]

To clarify, this issue is not related to the infinite loading bug reported here: #1223

Without Dark Theme:

Furthermore, Firefox itself is able to draw contents outside of its window: