Greasy Fork

In the waterfox 5.6.3 DevTolls console i see a always many request about:
https://accounts.youtube.com/_/AccountsDomainCookiesCheckConnectionHttp/jserror
They make error:
[HTTP/2.0 404 Not Found 5 ms]

It's related to your script?
Youtube seems wanted we connect with a high impatience.....
Can you do something against that ?

I test my profile to find which addon or script have problem.
When i use Firebug i notice many hangs and want understand why...

Re tested without greasemonkey userscript enable:
I see always these permanent request
So, that's not your script...
An idea?

As you've seen, it's not the script.
I had a laptop in hibernation since yesterday with WF running (with a youtube page opened). When I woke it up and opened the console, I saw some messages similar to what you're reporting here. But since then, reloading the page (with or without clearing cookies) doesn't seem to reproduce the problem.
I wouldn't pay too much attention to that unless it is slowing your browser. Which I don't think it does. The problem is with youtube, probably not an extension. Unless it is designed/configured to do something on youtube.com.

If you're not already using uBlock Origin, you should consider it. It can change your life. And you can use it to prevent some connections. But be carefull not to break sites' functionalities.

Thank!
I use uBlock Origin too, but about this "problem" i doubt to find something which don't break a functionality.
It's difficult after to remember some tweak made and introduce dysfunctional behaviour...

I have reloaded/ connect/disconnect/click "dismiss to connect to youtube", clear cache etc ...
Always these requests.
I don't know if they slow down waterfox, anyway, these connections are irritating .
But i imagine i can live with.
;-)

I always put comments next to the rules I add to uBO. I timestamp each modification and add the full url of the originating site (if usefull):

example:
! 20200123.2003 apparemment pas nécessaire puisque EasyP a 2 filtres maintenant (but since there is more than ping & img here... fu.. amazon)
amazon.com/1/batch/*



Maybe i can test that.
Not now, but...
Thanks for the tip.