Waterfox: Waterfow Classic 56.3 : Problem in YouTube Music (no drag possible in right playlist)

[decembre]

Test link:
music.youtube
I can't drag item in the list (right panel).
I see the drag cursor when i hover an item in the playlist, but i can't drag it.
Here a screenshot (with Waterfox classic 56.3):

Test in many different profiles:
Same problem.

In Firefox Quantum and Chrome:
All work fine.
Here a Gif screenshot (with Firefox Quantum) of the normal use:

PS:
There is too a problem with GitHub:
Nothing work when i want post an issue (for that i need to use Firefox Quantum):
No possible to drag a screenshot in the form
-Add link not working too

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[hawkeye116477]

PS: Solution for GH is already written on https://github.com/MrAlex94/Waterfox/issues/1790#issuecomment-709530207.

[decembre]

About Polly:
I have installed it, but no change about the problem with GitHub...
Same for YouTube Music.
How to use it ?
I follow the instruction:
"Once the page is loaded, open Polly's popup menu (the icon looks like a puzlle piece) and tick the Webcomponents-Bundle.js check-box. Reload the page, works again."

But if i change in about:config:
dom.webcomponents.enabled to "true"
Solve the problem.
For the YouTube problem (no dragging) too.
But if it possible i prefer a solution like Polly (if working)

[lfmnovaes]

I'm using Waterfox 2020.09 rn and I can't reproduce the issue u r experiencing. Win10 here, and I didn't do any "tweak".
Edit: just noticed that might be a "classic" problem.

[decembre]

Yes, seems a problem with only Waterfox Classic

[Jamesstevens-3rd]

About Polly:
I have installed it, but no change about the problem with GitHub...
Same for YouTube Music.
How to use it ?
I follow the instruction:
"Once the page is loaded, open Polly's popup menu (the icon looks like a puzlle piece) and tick the Webcomponents-Bundle.js check-box. Reload the page, works again."

yes but that's not all you must also put a tick in the Use request modification method for this domain the latest version is 1.5 and once I updated I had to untick Use request modification method for this domain restart the browser then go to GitHub and re-enable it for Poly to work. again

_TIP_: to restart Waterfox and keep all open tabs type about:profiles and click the button Restart Normally

_EDITED:_ for spelling and grammar