Yes, don't worry, your Firefox browser is working correctly. Problem is, though , that
max search requests are restricted to 10 000 per day, that's restriction by YouTube API.
When limit is reached, every user will get "Ups, something went wrong".
I noticed that limit is reached almost every day(close to midnight) since last month.
In order to resolve this problem, I will try to implement proxy server as backend, as soon as possible but it will take some time to develop.