shader error- cc.brightness.ip.jxs

joshua goldberg's icon

merely instantiating 'jit.gl.slab fa @file cc.brightness.ip.jxs' in
render context fa results in an error printed to the max window:
setting GLSL param: GL Error: Invalid operation

albook 1.67 early 2005, running 10.4.6, 128MB vram.

is there an error in the shader code? running latest jitter beta.
great job, btw, guys.

j