After some feedback i quickly added some performance improvements for the web tool (no changes with the shaders).
I prevent re-rendering of frames with static effects, as the image would stay the same and any effects that maintain pixel sizes, render at original image resolution making the performance stable even when zooming in. This should improve the overall experience with the tool as most examples start zoomed in at 3-4x scale.

But keep in mind:
Some shader effects might still be heavy on some machines/GPUs, especially when using large images. In the future i'll try some performance improvements of some shaders, but as of now, they are not optimized for real-time usage. Feel free to reach out if you want some custom solution for your game, if you like these effects.