Solution 1 :
Press the ALT and SPACE keys while you over the Lychee Slicer icon, and a little menu should appear
Solution 2 :
Use one of those options when you right-click on the Windows taskbar (not on the icon)- cascade windows- show windows stacked show windows side by side
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Solution 3 :
- Click on the Lychee Slicer icon in the taskbar
- Press the keys WINDOWS + SHIFT
- and while you hold the WINDOWS + SHIFT keys, use the arrow of your keyboard to move the windows (you will probably need to press a few times on the left or right to try to bring it back to your main screen, this manipulation moves windows from a screen to another screen