Unable to open designer / web app editor

[lui]

Im getting this error when trying to open the form in designer

[timl]

Hi @lui 

On rare occasions, these types of error can sometimes occur. I'd try again after a short while and hopefully, the problem may have gone away. If not, I'd close the browser and log back on again to see that helps.

If that fails, you can raise a support ticket by clicking the 'Create support ticket' button on the following page.
https://powerapps.microsoft.com/en-us/support/