[Enhancement] do not display sites as online/100% health if sites "Can't load the video on this Invidious instance"

[slrslr]

Trying to open YT video opens a list of proxies where one is yt.drgnz.club displayed as 100% health, yet it is false because it is not working, because that site https://yt.drgnz.club/watch?v=abcdef says:

Can't load the video on this Invidious instance. YouTube is currently trying to block Invidious instances. Click here for more info about the issue.

Please do not show instances which has this "issue" and can not load the video (currently). User is only mislead by the 100% health wasting the time.

[unixfox]

#44