@kautuk_sahni Unfortunately there is no way currently to achieve the above. The solution we came up with is to completely replace the RTE in the new Content fragment editor based on the example provided here: aem-uix-examples/cf-editor-custom-rte-field at main · adobe/aem-uix-examples · GitHubThis s...

All the UI extensions run inside an Iframe. This makes it not possible to use window.getSelection(). As the window is your application and the cursor is on experience.adobe.com. isActive property doesn't work either on the getCustomButtons.  So this does not work unfortunately. Kind regards, Reyn

Hi all, I'm currently working on an UI extension for the RTE in the new Content Fragment editor. I'm doing this based on the documentation provided here: Rich Text Editor Toolbar - AEM Content Fragments Editor Extensibility and also based on the examples provided here: GitHub - adobe/aem-uix-example...