I really love to use the shortcuts CTRL+Alt+ Arrow Left and CTRL+Alt+ Arrow Right to navigate through the code. It worked great on Ubuntu 18.04 and MATE but after migrating to my new notebook with GNOME and Ubuntu 20.04, I realized that the shortcuts didn't work anymore. Well, it worked via Navigate > Back and also showed the shortcut, but my fingers weren't able to do this...
I cried a lot. (Why God? WHY?)
Then I found this thread on StackOverflow Show archive.org snapshot . It wasn't just me. It seems that there are "ghost" shortcuts in the OS which can't be changed via UI.
But there is hope!
You have to use the default GNOME keymap in your RubyMine which maps the Shortcuts to Alt + Shift + Arrow Left/Right
And it works again! And, come on Shift is like Ctrl. ;-)
Alternative
gsettings set org.gnome.desktop.wm.keybindings switch-to-workspace-left "[]"
gsettings set org.gnome.desktop.wm.keybindings switch-to-workspace-right "[]"
If you ever want to restore the shortcuts, use:
gsettings reset org.gnome.desktop.wm.keybindings switch-to-workspace-left
gsettings reset org.gnome.desktop.wm.keybindings switch-to-workspace-right
