Can't use file picker on Firefox Dev edition 70.0b macOS 10.11.6

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#1

I hope this is the right place to post.
I couldn’t use the native filepicker for uploading a file on userinyerface.com .
Everytime Firefox crashed or froze.
Firefox Dev edition 70.0b, macOS 10.11.6

#2

you mean when clicking here?

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image.png1238×572 33.2 KB

it does work for me

#3

Yes, I’m talking about this. I don’t think it’s related to the site though

#4

It does it on other sites still in 72.0b so…