Security Alert - where did it come from?

I’ll put this topic in here because I don’t know the source of the warning.

I was using RSSOwl to reeds news feed, opened an item int the internal browser (it was from CNET) and this warning opened up
It isn’t serious, but there’s no clue as to which app. did it. In Opera the browser itself can do this; Avast WebShield does sometimes, but I don’t know if Comodo does.
AFAIK RSSOwl doesn’t, but if it runs on IE that might be the source.

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