If I have the IDE open and switch to hibernation because I interrupt my work, it is no longer possible to close the IDE when I resume work. And it is no longer possible to save an open project.
#Bugreport
Windows 10, Company Network
I think that this bug report is applicable: IDE might get into a non-functional state after OS sleep/awake cycle · Issue #2148 · arduino/arduino-ide · GitHub.
There is also Serial Monitor loses connection after PC sleeps · Issue #1895 · arduino/arduino-ide · GitHub for the serial monitor in case you encounter that.