New logstash error.
Notice: Undefined index: url in /srv/mediawiki/php-1.30.0-wmf.11/extensions/MobileFrontend/includes/specials/SpecialMobileLanguages.php on line 68
Has happened twice on ml.wikipedia.org and es.wikipedia.org:
https://logstash.wikimedia.org/app/kibana#/discover?_g=(refreshInterval:(display:Off,pause:!f,value:0),time:(from:now-7d,mode:quick,to:now))&_a=(columns:!(_source),index:'logstash-*',interval:auto,query:(query_string:(analyze_wildcard:!t,query:'message:%22Notice:%20Undefined%20index:%20url%22')),sort:!('@timestamp',desc))
Offending code:
```
foreach ( $page['langlinks'] as $code => $langObject ) {
if ( !isset( $languageMap[$langObject['lang']] ) ) {
// Bug T93500: DB might still have preantiquated rows with bogus languages
unset( $languages[$code] );
continue;
}
$langObject['langname'] = $languageMap[$langObject['lang']];
$langObject['url'] = MobileContext::singleton()->getMobileUrl( $langObject['url'] );
$languages[$code] = $langObject;
}
```
If a language URL is not there, there's no point in rendering it. So we should add an A/C.
It's not clear why a language URL should not be present... but not sure about value of investigating this further.