Use central jQuery
As with the extension-manager in #42197 also the lang-module should use the central jQuery in the contrib-dir. Just use loadJquery() for that.
Updated by Jigal van Hemert over 8 years ago
During the development of 6.0 (rather in the beginning) it was requested to bring jQuery into the core. Because we didn't want to break the record of the CMS with the most JS frameworks it was agreed that prototype/scriptaculous had to go. Also, there had to be a good API for including parts of jQuery and for version management.
Both requirements were not met and as a result the EM uses its own jQuery lib.
Please make issues for these tasks and only use the central jQuery library after finishing the other tasks.