When I try to launch the cornerstone editor it is showing a blank grey page.
And in the console it is showing “Uncaught (in promise) TypeError: Cannot read properties of undefined (reading ‘createElement’)”
Thanks for reaching out.
I suspect that it might be due to an improper update of Pro, I would suggest you deactivate and delete the Pro and re-install the version by downloading from your Themeco account and check if that resolves your issue. If that does not help, there might be some different reasons behind your issue. I would like to suggest troubleshooting the following common issue to help us to recognize the reason.
If you discover that an issue is coming from a custom code or 3rd party plugin, kindly consult with a developer or contact the plugin author. Please note that we do not provide support for custom codes and 3rd party plugins.
If none of the above helps, please give us access to your staging site in the secure note for further investigation, including: