Leaflet: 2 Finger zoom on Mobile does not work if 2 fingers placed at same time (Tested on Android + Firefox 79.0.5)

[FinduschkaLi]

• Zooming on map works only, if 2 fingers are placed on screen one after another.
• if both fingers are placed on screen at the same time, no pinch-zoom is possible.
• If i place first 1 and then the second finger and pinch to zoom / dezoom it works just fine.
• Double-tab zoom works normally

VERSIONS
Firefox mobile 79.0.5
Android 10 on Motorola Power
Leaflet 0.1.6 (see example code below)
Code where tested: https://leafletjs.com/examples/quick-start/example.html

REPRODUCE
Go to https://leafletjs.com/examples/quick-start/example.html on device, place both fingers simultaneously on the map and try to zoom -> should not work
Place first finger 1 and then finger 2 and try to zoom --> should work

FURTHER INFO:
Pinch zoom is not working at all on Windows 10 / Firefox 79, 64bit / Lenovo Yoga 520 with touch screen.

[IvanSanchez]

Possible duplicate of #7206. Also could be put under the umbrella of #7200.

[Yarjk32]

I have the same problem at Firefox for Android 79.0.5 (Build #2015758619). But I have Android 5.1 (Flyme 6.3.2.0G) on Meizu M3s. Before this Firefox version, I don't notice this problem.

[FinduschkaLi]

I am also almost certain, that this worked before the update to FFox
79...

[doconnoronca]

I used pinch to zoom the maps on my website https://www.transsee.ca/routemap?a=ttc&r=501 and after the recent major update of Firefox Mobile it no longer works.

[andwaal]

Same issues on FF 81.1.1 @ Android 10.0

[arggh]

Same issue on iPad (7th generation), iOS 13.3, Safari.

[arggh]

...and I seem to have solved my iPad issue by setting a CSS property touch-action: none; on my map container element.

edit: too soon. I still managed to get the map into a dysfunctional state.

Symptoms:

• Panning tries to scroll the page
• Panning gesture pans the map for a brief moment, but then stops
• Pinch zoom zooms the page, not the map

[Yarjk32]

In the last Firefox update, Mozilla had fixed this issue. More info here.

[IvanSanchez]

So this was being caused by an upstream bug that has already been fixed... closing this one, then.

Kudos to the Mozilla folks (i.e. @staktrace)