AFAIK, the chrome user agent switcher extension only changes the agent on a JS level. You can't change what is being sent to the server due to limitations in the extension API.<p>This explains the Adsense warning because the server-side part of the framework used (gwt) is seeing a different user agent than what the client part is seeing.<p>Granted, UA sniffing is bad practice on either client or server side, but if you do it and send content tailored for browser A and then see that, strangely, the client is actually browser B, then you are probably allowed to be confused and complain (better than failing in strange ways).<p>Also knowing that, it's unlikely that something on the server side is causing these connection reset issues because, as I just said: the server still sees a chrome user agent and producing a connection reset error (RST packet) requires connection level involvement (server or somewhere in between, but never the client browser, minus bugs).<p>In general: be very careful what error messages you see: the Adsense error is different from the gmail error which in turn is (likely) different from the connection reset issue.<p>Overall there is too much conflicting information to attribute malice or even just intent to Google here.<p>If I were in that users position, I'd check my firewall and/or proxy configuration (and try disabling HTTP pipelining if it's active in Firefox - it's disabled by default for a <i>reason</i>) as the problem is much more likely somewhere over there.