You can think of it, what you want, given their recent change in staffing MDN. But this repository opens up a new possibility to search the MDN content.
git clone https://github.com/mdn/content.git
away, I can employ other, more sophisticated tools to that task.
ack, together with
find, will help me cut to my desired information more quickly:
# find pages with the title "align-content"
$ ack ^title:.*align-content
# find mentions of @media and "pixel-ratio"
$ ack '@media.*pixel-ratio'
# find all files regarding the HTMLImageElement:
$ find -ipath '**htmlimageelement**'
If that should somehow not be enough, you are now able to build your own custom web frontend (with search) ontop of those files.