Firefox doesn't recognize [data-glide-el="track"] attribute on loading

[Epizefiri]

Hello there,
I'm developing a solution to use Glide.js inside Grapes.js ( A nice block editor ).

Grape.js is using iFrames, when i try to load a slider inside an iFrame I get these two errors on my firefox console

[Glide warn]: Could not find track element. Please use [data-glide-el="track"] attribute.

and

Uncaught TypeError: i.track is undefined

This is weird because the attribute is in the correct position ( and everything works on Chrome ).

If i remove the condition

if (exist(t)) { on row 1610 of glide.js 3.6.1 my sliders are working fine.

[Epizefiri]

#675 I see that the same condition have been discussed here

[jedrzejchalubek]

@Epizefiri Could you prepare MR that removes this exist check entirely? It was purely for development experience to provide a nice error instead of "something is undefined" but it looks like it causes more troubles

[Epizefiri]

@germandmg did it for me #695