How can I disable Alt+Space native hotkey in Windows 10?

Alt+Space hotkey is taken by Windows system by default.

However with the help of a 3rd party solution you can override this setting and take control over Windows by not letting them to steal the hotkey combination.

  1. Download Autohotkey and install it.
  2. Create a new file in Notepad or your default editor and insert these 2 lines:

    ; it allows to make a rule which is applied only when windows contains the given title
    SetTitleMatchMode, 2 
    
    ; obviously below you write the title that is contained in your program's window 
    #IfWinActive, Kdenlive
    !Space::Return ; ! stands for Alt key
    
  3. Save it somewhere easy to access it as Whatever.ahk (and not as .txt)

  4. Double click on it (or Run as Administrator) and it will trigger AutoHotKey to execute it and have it loaded. Now the Alt+Space hotkey does not call the Windows default actionwhen is hit in a window with the given title (Kdenlive).

I suggest to put it on your startup programs for not having to execute it manually each time you reboot your system.

You can find more information on how to program hotkeys in AutoHotKey by scripting on https://autohotkey.com/docs/Hotkeys.htm