I have a canvas component that contains a tab navigator, and each tab consists of a canvas. The tabs trigger scrollbars if their contents overflow the sizes of their containers. The problem is that the scrollbars on the tab canvases do not release focus after dragging the scrollbars. I can release the mouse, but further movement of the mouse triggers movement of the scrollbar. The problem is intermittent and I have not been able to determine what is causing it. Clicking the scrollbars, the scrollbar arrows, inside the tabs, and outside the tabs will sometimes release the scrollbar, but subsequent mousing over (NOT clicking) one of the scrollbar arrows will then cause the scrollbar to move again. It's as if the mouseUp event never fires. I have not seen any references to anyone else having this problem anywhere. If you have ever seen this, please let me know.