The code would toggle between expanded and collapsed every time the mouse moves over the item (after the autoExpandDelay), which was unusable. As reporters point out (and I fully agree), collapsing the item under the mouse is never wanted. I attempted an auto-collapse when moving out of the current subtree, but that was not usable either: when moving the mouse down, the auto-collapsing of a previous sibling means that the item we're targeting has suddenly jumped up, it's a frustrating experience trying to aim for a moving target. The only behavior that is usable is the most simple one: auto expand, never auto collapse. Fixes: QTBUG-2553 Pick-to: 6.8 Change-Id: I2c56dd668b2df4ec23bbbe829da6e8cdd049f376 Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io> Reviewed-by: Christian Ehrlicher <ch.ehrlicher@gmx.de>