Amastaneh blog is a discussion site on software development, programming, algorithms, software architectures,software run-time errors and solutions from software engineers who love building great softwares.
February 22, 2015
The prefix attribute on head for Open Graph is missing
Error: The 'prefix' attribute on <head> for Open Graph is missing
Just add this prefix to your head element <head prefix="og: http://ogp.me/ns#">