Ubuntu 13.4 64bits
Intel Mobile GM965/GL960 Integrated Graphics Controller
My glxinfo gives:
OpenGL vendor string: Intel Open Source Technology Center
OpenGL renderer string: Mesa DRI Intel(R) 965GM
OpenGL version string: 2.1 Mesa 9.1.1
OpenGL shading language version string: 1.20

When opening a WebGL page in FireFox as well as Chromium with "#version 110" (or anything higher than 100), I get an error:
"Error compiling shaderERROR: 0:1: '110' : version number not supported"
How is this possible?
The GLSL version is 1.20.