HypersomniacLive: DyNaer is already frustrated with it. It seems to be implemented the same way as the GOG Galaxy banner, so if one clears cookies/cache it keeps returning.
Alright, made a quick update with an option to hide that notice. I made both options a simple checkbox to hide or show (if you've already hidden the banner then you'll need to re-apply the setting).
On Firefox this should persist even if cookies are deleted, because the settings are stored in SQLite. I haven't actually tried having GOG cookies delete after every session on Chrome, but that uses local storage for keeping the settings so it might be a problem. I'll check out what happens when I get the chance and look into migrating the Chrome extension into extension storage instead for a version in the near future if that's needed.