There are several solutions to this:
1) You can insert link to js file, but not the content of the js file. But it will not be cached.
2) Use PHP block and insert code like, this:

return " HTML code with tabs or other UI elements";
What I was asking for, was something that the average Dolphin user could do in page builder.
I believe that average Dolphin users don't require this.
Advanced users can use one of the techniques I described before.
I just discovered a mod by Deano, Head Injections, that makes this all really easy, so I take back this request.
If it's not an option they indeed can't do it... I have wanted this option since day one... Lead them to the option and they will take it... IMHO...
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