Issue while working with Shader Mask

[justbetterApps]

I am trying to use child blur method to blur out the bottom of an image having fading edges using shader mask, but when i wrap this image with inspire child blur type, the blur doesn't draw on the image only if i remove the shader mask does it work, so the only option i am left with is to use the backdrop blur which seems to have some performance issues, so i am looking for any workaround for that, looking forward from you on this