Shader stopped working on every platform, but still looks fine in editor.

Unity Engine
1

I’ve a custom but simple shader which (apparently spontaneously) has stopped working everywhere except the Unity editor preview. Specifically, the FlashAmount property tween has no visible effect. (Android/Windows/Vulkan/GLES/DX11) Does anybody have an idea why this would happen? Did something change with 5.6.1? The shader code hasn’t changed in a couple years…

Has anybody ever encountered a similar problem?

3086777--232584--editor_flash.JPG
3086777--232584--editor_flash.JPG726×562 26.7 KB
3086777--232585--no_flash.JPGonly the corresponding particle effect is rendered

3086777–232575–borked.shader.txt (1.45 KB)

2

I found out that the below message is never displayed in the editor, but displayed when I run a build. :rage:

if (!GetComponent().material.HasProperty(FLASH_AMOUNT))
{
StatusText.Instance.Add(“I literally can’t even”);
}

I’ve no idea whats going on.