I just started using O and on 3 computers trying to get the same setup. On only one of those installations, my Extensions sidebar icon has a red notification badge. I have tried and tried but cannot find any notification to address (like the android Amazon icon)! I have the same extensions on all the computers: raindrop.io, 1password extension (with install google extensions), Opera Ad Blocker (why is that there? isn't it built in?).
ASIDE: When the Chromium MS Edge came out I jumped on that for a while, but after some issues decided to try Opera...this thing is perfect. I'll be telling all my friends to dump Chrome!