The MobileFrontend extension shouldn't special-case the main page. Currently a lot of the logic and infrastructure is based on a { if isMainPage() } { else ... } model, which is silly and unnecessary. The extension code should be flexible and adaptable to any page. A few tweaks might be necessary for the main page, but there doesn't need to be a completely different system in place for it.
Steps to achieve this
[x] Audit all wiki pages which use special cased main pages
[x] We should set $wgMFSpecialCaseMainPage = false for any projects currently not using mobile main page special casing
[x] Deploy TemplateStyles to render this code obsolete
[x] Community engagement - T138622 and T246401. All mobile main pages need to be updated to not use the `mf-` prefix using only the `nomobile` where necessary. See wikidata.org and English Wikipedia for examples.
[x] Main page special casing turned off for all projects with $wgMFSpecialCaseMainPage
[] Remove special casing code from MobileFrontend
# Sign off steps
[x] Addzip file of all projects before and after (@jdlrobson has this)
Screenshots before and after for projects are listed here:
https://drive.google.com/drive/folders/1n4xB7Tk1klEnlw1EN-bSOReRQf791Jc-?usp=sharing