Can't connect the app with the browser extension in ubuntu

Hi Ali o/ Thank you for helping. I ran the commands in terminal but after the "sudo gedit custom_allowed_browsers" where i got a new window, inserted "vivaldi-5.5.2805.35", saved and came back to terminal shock full of warnings. I took a screenshot and attached to this message. The language is norwegian but i think you get the meaning.

In afterthought, maybe i should have used the puctuation marks ( . ) when entering letters and symbols in terminal?