by icon you mean favicon? or what kind of icon? if for example you have domain.net when in that folder domain.net/dir/dir/file.extension the root directory with favicon.ico or gif or whatever you want will have the same favicon if the page won't link to another one.. thats the secret.. if you have a subdomain, like sub.domain.net when the favicon needs to be in the root/sub directory..
So I guess your question is if is it possible to have the same favicon for all your pages for your account including subdomains using htaccess? it can always be done with simple HTML by using <link rel="icon" href="favicon.gif" /> and the href can have a full path or the path to your favicon file.. I don't really think that you need to use htaccess here?
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