With Cocoa style, Scrollbar will dismiss QToolbar when actions has both text and icon.

Minimum reproduction code https://github.com/SourceReviver/qt_scroll_bar_toolabr_bug

Scrollbar will dismiss expanded QToolbar if the toolbar has both icons and texts.

The problem only occur on default cocoa style.

See the attachments:

With cocoa style, the toolbar stopped the expanded state when the cursor hovering over the underlying scrollbar.

cocoa_style.mov

With fusion style, everything is normal. The toolbar is still expanded when the cursor  hovering over the underlying scrollbar. However, the cursor shape changed to resize is still werid (This occur on Linux too).

fusion_style.mov