Marius Dumitru Florea it took me a while but in the end I discovered what was the problem. It's not a bug in ChartJS, we already listen on xwiki:dom:updated events. Apparently it's a feature in XWiki, we have this option in WYSIWYG editor administration: . This is not set by default, and once it's set then I don't have the bug anymore. The reason is that this option prevents from loading the JSX hook in https://github.com/xwiki/xwiki-platform/blob/master/xwiki-platform-core/xwiki-platform-ckeditor/xwiki-platform-ckeditor-ui/src/main/resources/CKEditor/ContentSheet.xml#L76-L78. But I'm a bit surprised about this behaviour, since as you said yourself we don't use that flag for the inline editor: making the JS hook working properly in the inline editor...
So at this point it feels like either we should also use that config in the inline editor, or we should remove it completely. WDYT?
