All PHP deprecations have been cleaned up from MobileFrontend except:
- setIsMainPage() method -- handled in T32405: [EPIC] MobileFrontend extension should stop special-casing main page
- InlineDiffFormatter::class -- which is pending removal here -> https://gerrit.wikimedia.org/r/c/mediawiki/extensions/MobileFrontend/+/556811 ✅
Most of the work was tracked in T221982: [Tracking] Avoid use of deprecated core classes, class methods, configs, and constants in MF. This task is to complete the work in the aforementioned ticket.