This global was deprecated on
https://gerrit.wikimedia.org/r/#/c/113159/2/resources/mediawiki/mediawiki.jqueryMsg.js,unified
but is still in use on
https://github.com/wikimedia/mediawiki-extensions-TimedMediaHandler/blob/f9df84a9a1bf5760a10c5448c9784f54972851c5/MwEmbedModules/EmbedPlayer/EmbedPlayer.loader.js#L63
causing warnings like this:
'Use of "gM" is deprecated. Use mw.message( ... ).parse() instead'
on Portuguese Wikipedia.
Version: unspecified
Severity: normal