While every browser displays a tip you can exit the video you’re watching in Full Screen by pressing the Esc button, this message can be annoying if it stays for a long time and if you watch videos in Full Screen mode quite often, you may want to disable or remove that Esc full screen prompt, here is how that can be done in Vivaldi browser.
Disable Vivaldi’s ‘Press Escape key to Exit Full Screen’ Message
1. V icon > Tools > Settings
2. Webpages, under FullScreen mode, ucheck ‘Show Fullscreen reminder’.
To get the Full Screen prompt back, enable above option in WebPages settings.