buttonImGuiMouseButton index: 0 left, 1 right, 2 middle.
delayDelay in seconds after mouse release before reporting the delayed release.
True if the requested delay after the most recent mouse release has elapsed this frame; false otherwise.
delayed mouse release (use very sparingly!).
Typically use delay >= io.MouseDoubleClickTime, where io is the field view returned by ImGui.viewImGuiIO(ioHandle), and check the count for the same button. For the left button, test ImGui.viewImGuiIO(ioHandle).MouseClickedLastCount0 === 1.
This is a very rarely used UI idiom, but some apps use this: e.g. MS Explorer single click on an icon to rename.
Test for a mouse-button release after a delay.