When trying out mediawiki 1.33, i am seeing:
/w/load.php?lang=en&modules=startup&only=scripts&skin=timeless ConfigException from line 53 of /srv/mediawiki/w/includes/config/GlobalVarConfig.php: GlobalVarConfig::get: undefined option: 'EnableBlockNoticeStats' #0 /srv/mediawiki/w/extensions/MobileFrontend/includes/MobileFrontend.hooks.php(428): GlobalVarConfig->get(string) #1 /srv/mediawiki/w/extensions/MobileFrontend/includes/modules/ResourceLoaderFileModuleWithMFConfig.php(16): MobileFrontendHooks::getResourceLoaderMFConfigVars() #2 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderModule.php(727): MobileFrontend\ResourceLoaderModules\ResourceLoaderFileModuleWithMFConfig->getScript(ResourceLoaderContext) #3 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderModule.php(694): ResourceLoaderModule->buildContent(ResourceLoaderContext) #4 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderModule.php(830): ResourceLoaderModule->getModuleContent(ResourceLoaderContext) #5 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderStartUpModule.php(255): ResourceLoaderModule->getVersionHash(ResourceLoaderContext) #6 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderStartUpModule.php(438): ResourceLoaderStartUpModule->getModuleRegistrations(ResourceLoaderContext) #7 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderModule.php(727): ResourceLoaderStartUpModule->getScript(ResourceLoaderContext) #8 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderModule.php(694): ResourceLoaderModule->buildContent(ResourceLoaderContext) #9 /srv/mediawiki/w/includes/resourceloader/ResourceLoaderModule.php(830): ResourceLoaderModule->getModuleContent(ResourceLoaderContext) #10 /srv/mediawiki/w/includes/resourceloader/ResourceLoader.php(658): ResourceLoaderModule->getVersionHash(ResourceLoaderContext) #11 [internal function]: ResourceLoader->{closure}(string) #12 /srv/mediawiki/w/includes/resourceloader/ResourceLoader.php(670): array_map(Closure, array) #13 /srv/mediawiki/w/includes/resourceloader/ResourceLoader.php(751): ResourceLoader->getCombinedVersion(ResourceLoaderContext, array) #14 /srv/mediawiki/w/load.php(46): ResourceLoader->respond(ResourceLoaderContext) #15 {main}
In the logs, but in the js console i see "[6517215b23165c93329a295e] 2019-06-08 16:36:35: Fatal exception of type "ConfigException"".