Reading a value from an external file

This has undoubtedly been asked before -- I see a related post about files:

Saving variable in text file issue - Articulate Storyline Discussions - E-Learning Heroes

I know that security concerns have caused modern browsers not to support ActiveX objects.

Essentially, what I need is an environment variable.  I have a slide that calls a website page.  The URL is hard coded (https://www.whatever.com/whatever).  But depending on the internal server I want to talk to, I might want to communicate with http://someotherserver.com/whatever.

I figured I could read an external file and get the url value from that, set a variable, and then just use the variable for the url instead of the hard code.

Is there a way to do that in Storyline 3?  I know Storyline 3 is no longer supported, but it's what we've got for now.

Thanks