ADD CUSTOM BLOCKS (i.e iframe) and customise it like image i.e on double click it open assets options for video link in custom iframe block

WARNING READ and FOLLOW next 3 steps, then REMOVE them before posting the issueFollow CONTRIBUTING Guidelines https://github.com/artf/grapesjs/blob/master/CONTRIBUTING.mdDo a quick SEARCH first, to see if someone else didn't open the same issueAll relative statements/questions have to be filled/answered, otherwise, the issue might be CLOSEDJSFiddle Starter template https://jsfiddle.net/szLp8h4nCodeSandbox Starter template https://codesandbox.io/s/1r0w2pk1vl What are you trying to add to GrapesJS? Describe your feature request detailed Is there an alternative at the latest version?[x] Yes (des...