MediaWiki's guide on making skins currently recommends that skins are implemented using the Mustache template engine (which is possible in MediaWiki since 1.25, and the zordius/lightncandy Packagist package is listed as being installed in Special:Version as part of MediaWiki).
It reduces the reliance on PHP and might solve several issues tagged on this repository about deprecated functions.
MediaWiki's guide on making skins currently recommends that skins are implemented using the Mustache template engine (which is possible in MediaWiki since 1.25, and the zordius/lightncandy Packagist package is listed as being installed in Special:Version as part of MediaWiki).
It reduces the reliance on PHP and might solve several issues tagged on this repository about deprecated functions.