Hi,
I'm not sure if it's bug in Godot 3.4.2, but my sprites aren't viewable in the Editor Scene View. Maybe I've clicked something I'm not aware of, but from what I can see, they should be in screen. They were visible when I first created them.
Pressing Play for the selected animation does not show the sprites animating, however the game runs fine and you can see the sprite animations, just not in the editor.
Another issue, is that an animated sprite is shown, but when you change animation, it doesn't update or play in the Editor.
Invisibe sprite in Editor:

Can't change animated sprite in Editor, Animation does not play:

If I add new sprites with textures, they display fine, it's just my first initial sprites I created that are affected :(