Recently I have been successful getting Gem running over Chromium: http://chromium.sourceforge.net/
After disabling all of the non-chromium compatible extensions I could via compile time flags : ./configure --with-glversion=1.5 --disable-ARB --disable-NV
I was still having problems with glDeleteFramebuffersEXT and other frame buffer commands not being defined when I ran via chromium.
I didn't see a compile option that allowed me to disable these frame buffer commands, so I added this:
#undef GL_EXT_framebuffer_object
to src/Controls/gemframebuffer.cpp
after the includes.
and now gem works via chromium. Maybe the Gem developers could add [or suggest one that already exists] a compile time option to disable these commands, so that others might be able to use chromium with gem as well.
-Alex