Edit App Code without having to use SDKs

Ed_

The other day I wanted to make some changes to a popup in Map Viewer and the map search tool (not widget ) in Experience Builder. 

The only way to do that (please correct me if am wrong) is to first create an entire app on ArcGIS SDK for JS > then publish the app as a site on another site say GitHUb > then add the app as an item on AGOL > and then embed that app as an iframe to a desired app.

These seem like a lot of steps in order to make small changes.

I think it would be much more convenient to have the ability  to modify the app's code (be it formatting the layout or widgets and etc) with the help of a toggle/button. Basically to modify the app's code on the fly.