Yesterday I would have said they don't care about other platforms and compatibility issues. Today I'm not so sure. Anyway, looks like at least the GitHub has a

Yesterday I would have said they don't care about other platforms and compatibility issues. Today I'm not so sure. Anyway, looks like at least the GitHub has alternative font values: wf_segoe-ui_normal,"Segoe UI",Segoe,"Segoe WP",Tahoma,Verdana,Arial,sans-serif