Replace element with text with javascript (no jquery)
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I'm trying to create a link which has a dynamic value in it

    http://my.link/index.php?action=huh&id=X

The X is what i want to replace dynamically with javascript variable.
I don't want to use jquery for it.

AND, i do not want to replace the whole link because some part of URL needs to parsed by the template engine.
I think it'd be better if i inserted an element in place of X and replaced it with JS