https://bugzilla.redhat.com/show_bug.cgi?id=2240167
--- Comment #1 from fujiwara tfujiwar@redhat.com --- Workaround:
1. Menu -> Preferences -> Applets (or Run `cinnamon-settings applets`) and open "Applets" dialog 2. Select "Download" tag in the "Applets" dialog and find "Menu" applet. 3. Click "Configure" gear button on the "Menu" applet and open "Menu" dialog 4. Select "Menu" tag in the "Menu" dialog and find "Keyboard shortcut to open and close the menu" configuration in "Behavior" seciton 5. Click the default "Super_L" button in the confnguration and change another shortcut key likes "Print". 6. Close all dialogs
The you will find your customized setting is saved in $HOME/.config/cinnamon/spices/menu@cinnamon.org/0.json against /usr/share/cinnamon/applets/menu@cinnamon.org/settings-schema.json
Now you can use Super-space from the first typing.