About 17 errors a day on mediawiki.org
https://logstash.wikimedia.org/app/kibana#/dashboard/Reading-Web?_g=h@a7847a0&_a=h@dfd95ba
https://logstash.wikimedia.org/app/kibana#/doc/logstash-*/logstash-2020.06.16/clienterror?id=AXK9-V69ZmYAikdJytJn&_g=h@b62398b
```
at Object.OO.ui.Element.static.getRootScrollableElement https://www.mediawiki.org/w/load.php?lang=it&modules=...&skin=minerva&version=1mcax:275:407
at Object.OO.ui.Element.static.getClosestScrollableContainer https://www.mediawiki.org/w/load.php?lang=it&modules=...&skin=minerva&version=1mcax:276:193
at OoUiPopupWidget.OO.ui.mixin.FloatableElement.togglePositioning https://www.mediawiki.org/w/load.php?lang=it&modules=...&skin=minerva&version=1mcax:315:93
at OoUiPopupWidget.OO.ui.PopupWidget.toggle https://www.mediawiki.org/w/load.php?lang=it&modules=...&skin=minerva&version=1mcax:333:376
at showTipsy https://www.mediawiki.org/w/load.php?lang=it&modules=...&skin=minerva&version=1mcax:81:817
at https://www.mediawiki.org/w/load.php?lang=it&modules=...&skin=minerva&version=1mcax:83:254
```