Vivaldi as standard browser: Does not work
If I click any link in my mail client (Postbox) the system does not switch to the screen where Vivaldi is located. The mail client screen remains activated ! This is not the expected effect.
Does clicking links in other apps bring up Vivaldi? If so, then it's an issue with Postbox (which is a great piece of software, by the way).
The same effect in Apple's standard Mail.app for Mac