Seen on test wikipedia (iPhone)
https://logstash.wikimedia.org/app/dashboards#/doc/logstash-*/logstash-2021.05.06?id=QGq-Q3kBg_6mGHGhy2Cm
at VeUiContextItemFactory.ve.ui.ContextItemFactory.isEmbeddable https://test.m.wikipedia.org/w/load.php?lang=en&modules=ext.visualEditor.core&skin=minerva&version=1yie5:616:918 at VeUiMobileContext.ve.ui.LinearContext.getRelatedSourcesFromModels https://test.m.wikipedia.org/w/load.php?lang=en&modules=ext.visualEditor.core&skin=minerva&version=1yie5:610:310 at VeUiMobileContext.ve.ui.LinearContext.getRelatedSources https://test.m.wikipedia.org/w/load.php?lang=en&modules=ext.visualEditor.core&skin=minerva&version=1yie5:609:117 at VeUiMobileContext.ve.ui.LinearContext.isInspectable https://test.m.wikipedia.org/w/load.php?lang=en&modules=ext.visualEditor.core&skin=minerva&version=1yie5:608:614 at VeUiMobileContext.ve.ui.MobileContext.isInspectable <anonymous>:57:466 at VeUiMobileContext.ve.ui.LinearContext.afterContextChange https://test.m.wikipedia.org/w/load.php?lang=en&modules=ext.visualEditor.core&skin=minerva&version=1yie5:607:659