shell: Crashes on screen rotation

Update: This is fixed with a hack for now !458 (merged) Keeping this open in order to get a proper fix.

The shell seems to crash when the screen is rotated:

zwlr_layer_surface_v1@74: error 1: the layer surface has a width of 0 but its anchor doesn't include the left and the right screen edge
The Wayland connection experienced a fatal error: Protocol error
QQuickItem::stackBefore: Cannot stack QQuickRectangle(..., parent=..., geometry=0,0 0x0) before QQuickPopupItem(0xffff95c01560), which must be a sibling