flickering in Firefox

[teenriot]

The demo is flickering between colored and grayscale in
Firefox 56.0 (32-Bit) (tested with Windows 7)

[mountainash]

Even when using fadeAnimation: false as suggested in the README?

[ghost]

I've added fadeAnimation: false as suggested, but I also have the same issue as mentioned above.
var map = L.map('map', {
center: [55.958, 11.635],
zoom: 7,
minZoom: 7,
maxZoom: 15,
fadeAnimation: false
});