Well, I've gone back to this problem a couple of times since you posted it, & I think I've now replicated something which may be the same.
I often run AdBlock Plus & NoScript add-ons for Firefox, so had to turn them off first. I then clicked the Support link & still didn't get your re-direct problem (though, of course, I now got all the usual fixed position ads showing around the webpage).
After repeating the test by going to the Support page many times, I have on a couple of occasions now been re-directed to an advert page. It wasn't a major problem though - there is a Skip This Ad link at the top which will immediately get rid of it. I know that different adverts are served at random on x10's pages, so this could explain why the re-direct has only happened a couple of times.
Is this the same as you are experiencing, or do you get re-directed every time, & without the Skip This Ad link at the top? If you get it every time, then yes, you may have picked up some adware. It is always worth scanning one's system regularly for malware anyway, so why not do it now to see if you have picked up something?
Note: the adverts served by x10 produce a very small but useful income, which helps a little towards supporting the Free service. So I wouldn't advise you block the adverts if want to help keep this service free. I try to view them & even click them occasionally, though I must admit I find the Inline ads particularly annoying because they obscure what you are trying to read, every time your mouse inadvertently passes over one of them. Hence, my use of the Firefox add-ons which allows me to control when, & what, I want displayed.
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