Editing an empty gallery results in a javascript error

[Chouby]

How to reproduce?

1. In the classic editor, create a post with a gallery with one image and save the post.
2. Go to the media library and delete permanently this image.
3. Go back editing the previous post. The gallery displays "No items found".
4. Attempt to edit the gallery and check the browser console.

Here is the error displayed:

Uncaught TypeError: Cannot read property 'args' of undefined
    at n.<anonymous> (media-views.min.js?ver=5.8-alpha-50521:2)
    at f (underscore.min.js?ver=1.8.3:2)

and the trace:

(anonymous)	@	media-views.min.js?ver=5.8-alpha-50521:2
f	@	underscore.min.js?ver=1.8.3:2
setTimeout (async)		
(anonymous)	@	underscore.min.js?ver=1.8.3:2
p	@	backbone.min.js?ver=1.4.0:2
f	@	backbone.min.js?ver=1.4.0:2
c	@	backbone.min.js?ver=1.4.0:2
n.trigger	@	backbone.min.js?ver=1.4.0:2
(anonymous)	@	media-models.min.js?…r=5.8-alpha-50521:2
c	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
fireWith	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
(anonymous)	@	wp-util.min.js?ver=5.8-alpha-50521:2
c	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
fireWith	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
l	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
(anonymous)	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
load (async)		
send	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
ajax	@	load-scripts.php?c=0…r=5.8-alpha-50521:2
s.ajax.s.ajax	@	load-scripts.php?c=0…r=5.8-alpha-50521:5
(anonymous)	@	wp-util.min.js?ver=5.8-alpha-50521:2
s.Deferred.s.Deferred	@	load-scripts.php?c=0…r=5.8-alpha-50521:5
send	@	wp-util.min.js?ver=5.8-alpha-50521:2
sync	@	media-models.min.js?…r=5.8-alpha-50521:2
fetch	@	backbone.min.js?ver=1.4.0:2
more	@	media-models.min.js?…r=5.8-alpha-50521:2
more	@	media-models.min.js?…r=5.8-alpha-50521:2
edit	@	media-editor.min.js?…r=5.8-alpha-50521:2
edit	@	mce-view.min.js?ver=5.8-alpha-50521:2
edit	@	mce-view.min.js?ver=5.8-alpha-50521:2
onclick	@	plugin.min.js?wp-mce-49110-20201110:1
c.fire	@	tinymce.min.js?ver=49110-20201110:2
fire	@	theme.min.js?wp-mce-49110-20201110:1
o	@	theme.min.js?wp-mce-49110-20201110:1
C	@	tinymce.min.js?ver=49110-20201110:2
d	@	tinymce.min.js?ver=49110-20201110:2

[antpb]

Adding this to 5.8 so we can investigate further and work towards solving this. Thank you for your report!

[Hareesh Pillai]

Thanks for the bug report, @Chouby.

Underscore library was updated in #45785. However, the error still persists.
I'm able to reproduce this error before and after the update.

[JeffPaul]

With 5.8 Beta 1 next week and no patch/PR on this ticket, I'm going to punt this to Future Release. Once a patch/PR is available this ticket can be added back to a numbered milestone.

[Mista-Flo]

I'm not sure I understood steps 3 and 4, I went back to the post, either edit the broken attachment or try to open the media library through add media button but it doesn't output any error, it's just an empty library. (tested on trunk)