Question 2D emission shader not working

I'm trying to create a simple emission shader for Texture2D sprites based largely on Brackeys's tutorial. It seems like this should work, and yet the Main Preview remains blank...
...and nothing renders when I use the shader in-game:
I've gotta be missing something here, right?

 

1. Do you have a Global Volume with Bloom? I'm not seeing it in your hierarchy.
2. You're using an Image component not a SpriteRenderer. Try a SpriteRenderer. Bloom is applied before UI typically. See the order within Frame Debugger's: Post-Processing preceeds UGUI.
3. Why are you subtracting OneMinus alpha? The tutorial doesn't do this.

 

1. Yes.
2. I'm trying to apply a bloom effect within the game's user interface; this means using canvases. Is this simply something Unity can't handle?
3. Shader Graph has a bad habit of displaying garbage where a Texture2D's alpha is 0. This fixes it.

 

I suspect this is the problem. The workaround is to do something custom but unfortunately I haven't done that. If you were to ask in General Graphics someone should be able to instruct you how post-processing could be applied to UI or a workaround.

 

Any input from Unity developers here? Does URP simply not support post-processing of objects within Canvases? (If so, that seems like a pretty enormous oversight!)

 

well this is very old but in case anyone else stumbles across it, you need to change the canvas render mode. The default is Screen Space - Overlay. Change it to Screen Space - Camera. Then you can use post processing effects like bloom.