I am setting up my GitHub page and chose one of its theme. I want to also add some other features, e.g. MathJax. So I need to insert some <script></scripts> tags into the <head></head>. The only way I figure out how to do it now is to copy the theme’s _layouts/default.html to the local repository and insert a {% include head.html %} into its <head></head> tag, with _includes/head.html where I put the tags I want to insert.
This seems like of heavy handed because now I have to keep my local _layouts/default.html in sync with the theme’s version manually. Is there a way to insert header without keeping a local copy of of the default layout? Or does this has to be change on the theme’s side?
Thanks.