Slippery Stuff...
I too have a firewall. If I disabled messenger it wouldn't send me all those nice messages from 'Black Ice' when I'm under attack. Black Ice tells me whenever I get a probe but since the browser is allowed to access the internet, the firewall cannot keep out all executable code. There's still all those hidden bugs - some adverts and even web pages have image areas containing no visible information, but they hide executable code to mine your hard drive for information. [Have you ever noticed those pages that scroll down for dozens of lines below the last text? View the source code and you'll see it isn't really blank...] The firewall doesn't block these, but as long as it tells me immediately whenever unknown code attempts to execute itself, messenger pop-ups are useful.
The problem is, wonderful sites like this one depend upon advertising revenue to keep going. I suppose intrusions, or at least attempted intrusions, are the price we pay for our little pleasures.
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Through difficulties to the cinema