Ok, so I have done as suggested by Gwen-Dragon, and the suggestion has been moved to the Waiting Area of Comodo's Forums.
Not sure if this is the best place to post this?, but here is a link to the waiting area, for anyone who wants to upvote this.
https://forums.comodo.com/index.php?topic=118148.new;topicseen#new

The more votes it gets the more likely they are to include support for Vivaldi, so please any Comodo users go to the link and vote for Vivaldi support.
As with any forum you must register, but easy and worthwhile.
Cheers 🎨