LibO sometimes won't start up

Twice in the last few days, LibO has not started up. Double-click on the icon, or a document, or right-click on the icon and select Open - none of them work. It seems to happen when the machine has been sleeping, and a reboot cures it ( but is a major nuisance). It might have started happening following the latest Windows update on 12 April.

Has anyone else seen this behaviour?

I had this behavior after some crash of LibO, there stayed some part of Libre in memory and I had to press Ctr+Alt+Del and kill it, so “cure” was without reboot.