Interesting point you make.
Indeed, IE4 and IE5 had Microsoft supported add-ons to do so (the IE5 Web Accessories), but they don't work in IE6. Very regrettable, and you're not the only one who thinks so.
I don't have Mozilla at hand here, but it might be that (as a successor to Netscape) it offers the same function. Just download full Mozilla or Mozilla Firebird from www.mozilla.org and check. It's a full featured modern browser, and a good replacement for IE, generally.
Regarding IE, I found this reference http://philringnalda.com/blog/2002/02/ie6_may_be_tolerable_after_all.php in a few minutes with google (searching for "open frame in new window", which isn't exactly a very difficult search term for this problem). It seems to offer the full solution to your wishes, in at least two ways. Unless I'm very mistaken, I don't see 'countless hours' of searching involved.
I would appreciate feedback about your experiences. I consider turning to IE6 sometime myself (although it won't be possible now on my old Win95 machine) and would certainly like to have this feature installed again.
Kees
I use Netscape as my main browser because it has a number of features which IE does not. One important feature to me is the ability to open a frame in a new window by using the right mouse button. I have seen other users of IE have this function on their right mouse button but I do not have it. I've done countless hours searching on the net to see if there is a posted fix for this problem but I haven't found one yet. I run Win98se and IE6. Does anybody know of a solution?

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