Post Processing and Unity WebGL

 A common question asked several times about unity post-processing and WebGL that why post-processing is not working on my browser or some of the post-processing features are not working in the browser: The main reason is that post-processing works with WebGL 2 (Unity Forum). Unity WebGL Post-processing doesn't work on WebGL 1. If your browser and GPU support WebGL 2.0 then, PPS (Post Processing stack) should work within your browser but with two limitations. Unity Supports graphics API WebGL 1 and WebGL 2 and if Graphic API settings are set to auto then, WebGL 2 will try to run first (if supported in the browser). Please see the below images to check or enable WebGL 1 or WebGL 2 settings in unity :

How to check WebGL2 Support

Remember WebGL 1 is based on OpenGL es 2 and Webgl 2 uses OpenGL es 3.   You can even check your browser compatibility on these websites that it supports WebGL 2 or not

1. can I use webgl2
2. WebGL report v2

You can even write c# code to enable/disable specific settings like Post-processing support based on WebGL 1 or WebGL 2 version. by using SystemInfo.graphicsDeviceVersion classes