(In reply to Daniel Exner from comment #78)
> >10536: message: major api error 1: GL_INVALID_ENUM in glCompressedTexImage2D(internalFormat=0x8c4d)
> >10536 @1 glCompressedTexImage2DARB(target = GL_TEXTURE_2D, level = 0, >internalformat = GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT, width = 64, height = >64, border = 0, imageSize = 2048, data = blob(2048))
> >10536: warning: glGetError(glCompressedTexImage2DARB) = GL_INVALID_ENUM

Looks like you may be missing GL_EXT_texture_compression_s3tc. Do you have
libtxc-dxtn(-s2tc) packages installed?