Mouse hover effects never stop

Sometimes, after running Windows 10 for a day or a month, the taskbar starts exhibiting a weird behaviour. You know when you hover a taskbar item with the mouse, it gets that hovered appearance and shows a tooltip after a moment. Both disappear when the mouse moves out of the taskbar. But every now and then, the effects start to remain there. I move the mouse over a taskbar item and gets the hover effect. Then I move it out again, but the hover effect remains and the tooltip also appears. Explorer won't recover from this state.

I have no idea where this comes from. Is that a Windows Explorer bug that everybody has? Does 7+TT cause this? It's one of the apps that are more tightly hacking the Explorer process. The other one here is T-Clock. I need both so I can't tell whether it would be better without either of them.

Just asking if anybody else has this bug behaviour.

To resolve it, I need to restart Explorer. I've written a batch script for that. But Windows 10 has become more and more unstable over time. GUI updates are drawn slower and slower since about a year. A fresh reinstall doesn't help (Windows feature upgrades are broken anyway, don't use them). I have to restart Windows every few days now. Windows 2000/XP were probably at the peak of Windows' reliability. Now it's going down again.