Right now there are two documentation pieces about the configuration variables on MobileFrontend and they are out of sync (which is normal and was bound to happen).
Let's agree on a single source of truth for documentation, either the README of the extension in the repository or the mediawiki.org/wiki/Extension:MobileFrontend and link from one place to the other.
My proposal would be to make the documentation on the repo the canonical place to check the configuration variables given it is versioned with the code, so given a version of the repository it is easy to see the documentation of the configuration that applies to that version.
If so then:
 Sync mw.org config docs with the README.md (for example the wiki has `$wgMinervaAlwaysShowLanguageButton` but not the README)
[x] Remove the configuration table from mw.org, link to the configuration portion of the README in the wiki (to [[ https://phabricator.wikimedia.org/diffusion/EMFR/#configuration-options | diffussion ]] and [[ https://github.com/wikimedia/mediawiki-extensions-MobileFrontend#configuration-options | github ]])
 Make a nice markdown format for the configuration variables, like the table, but in markdown so that it is easier to read.