The timecorrection preference on Special:GlobalPreferences currently doesn't have a globalize-this checkbox, but it should.
|mediawiki/extensions/GlobalPreferences : master||Globalize preferences that specify class instead of type|
This is caused by preferences that set 'class' instead of 'type'. On enwiki, there are 12 such preferences (some of them are just UI elements):
|timecorrection (which this bug requests)||HTMLSelectOrOtherField||should be global|
|cirrussearch-pref-completion-profile||CirrusSearch\HTMLCompletionProfileSettings||should be global|
|betafeatures-auto-enroll||NewHTMLCheckField||should be global|
|several beta feature checkboxes||HTMLFeatureField||should be global|
|echo-subscriptions||HTMLCheckMatrix||should be global|
echo-subscriptions is extremely problematic because it's a composite form element representing multiple preferences that are stored separately.
I think I'm going to create a whitelist of classes for now. Not sure what to do about Echo preferences though, will open a separate bug for it.