I am pretty sure that the workaround is not quite right, at least on my Linux+ATI.
The magnified panda feet are caused by the unnecessary
light=base.makeCamera(LBuffer)More important, only the teapot casts a shadow. The panda does not.
I am guessing that it is a problem with tex2Dproj() in the shader.
I have started a new topic, in case other ATI+Linux people are getting the same thing, or have better ideas than me.
https://discourse.panda3d.org/viewtopic.php?p=16998#16998