How to remove shortcut from your left win

I'm using my win key for switching keyboard layouts (because why the hell would you need to press alt+shift when you can just press win). So obviously the default shortcut connecting it with the start menu is not ok for me. I mean it makes sense for Windows users, but I'm using Linux for probably 10 years now, I use the start menu only to suspend the machine. For anything else I use alt+f2. So it's redundant and nonsensical. 

The major problem  is that when you assign the left win to the layout switcher, it doesn't automatically unassign it from the menu. So to do that, you need to:

You need to modify the kwinrc file in ~/.config/kwinrc

Group

[ModifierOnlyShortcuts]
Meta= 

 and then then 

>qdbus org.kde.KWin /KWin reconfigure

or 

kwriteconfig5 --file kwinrc --group ModifierOnlyShortcuts --key Meta ""

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