Fast switch input source via CapsLock button in Ubuntu 17.10

I updated my Ubuntu version to 17.10 and I want to configure switching to next input source via CapsLock button. I tried to set CaspLock in keyboard setting, but I cant because nothing happening.

I did actions explained here How to switch input language on Caps Lock in Ubuntu 15.10 Gnome 3.16 and it works, but now when I switching input source I see a pop-up (like as pop-up that shows switching application windows) and must wait a few seconds until it disappears.

How I can resolve my problem?

Solution 1:

By trial and (a lot of) error, this works for me (I'm not sure whether the first three steps are required).

1. Open Settings (the default system setting app).
2. Go to Devices -> Keyboard and press Reset All....
3. Close the Settings app.
4. Install gnome-tweak-tool and open it.
5. Go to Keyboard & Mouse -> Additional Layout Options
6. Seek for Switching to another layout and unchecked every options under that setting.
7. Restart the Tweaks app.
8. Repeat step 5-6 again, only this time make sure you check the one and only Caps Lock option.
9. Close the Tweaks app, now you should use the caps lock button to switch language without popup menu to delay the input :D