ShowURL with headers

I’m trying to link to an external site using ShowURL and provide some basic headers in the request. I don’t want to do this as a URLConnection because I want the browser itself to make the request and show the page. Is this possible? Probably via Javascript?

only the URL gets passed. No parameters.

you could of course create an entry in your database, load an URL referencing that entry by passing ID in the URL. Then website loads with data from record, does something like sending post request in browser to load new page.

I’m also thinking I’ll have to do it that way and add a couple of extra steps. Thanks for your response.