For clarity: the link is to the generic "unsupported browser" landing page. Chrome (and Safari) are definitely "supported" browsers. Facebook just doesn't show their logos or provide a download link to them.
So the "you're" bit is vacuous. They don't mean your browser. They don't [functionally] mean any web browser. The page makes a statement, but we need to interpret that statement IRRESPECTIVE of our considerations of how it is generated/produced.
Safari I don't know, are FB obligated to inform people of every possible choise? Nope, they aren't. Now let's discuss something more interesting than this dull facebook page!
You know that, but there's no guarantee whatsoever that someone landing on this page knows that.
It's in FB's best interest to inform people of what works and what doesn't. They certainly don't test every single browser out there, so putting the browsers they test on onto this page keeps users on the happy path.
It isn't malicious, it isn't "stupid." It's "corporate." ("We'll fix it later.")
Interestingly, that page doesn't mention Opera.
Although interestingly, if Opera accounts for ~2% of FB users (big if), then FB would have 16MM Opera users. Using the average of $4/user/year, that means Opera generates $64MM for them. That would be more than enough to justify throwing a few devs at.
Edit: Also curious is the pointless URL that page has. I would have thought FB would be using basic SEO on their help pages, so that someone googling "facebook supported browsers" would have a better chance at ranking first (it does for me, anyway). As an aside, the sub's page is actually the second result.
Any Web developer knows that now it would take intention, effort, not to support Webkit browsers (Chrome, Safari). I mean, if we take your interpretation, we should assume that laptops support, say, USB1, 2 and 3. They just _don't show their female ports_ on the panels.
Can we just call a spade a spade? Otherwise the whole page itself is nearly meaningless. "Support" becomes a meaningless word.
Moreover, that's beside the point. It's CERTAINLY fair to suggest that to say the least, without much analysis, we can say that this page implies that FB [intends] a better experience on browsers which are not Chrome or Safari. THAT is fair.
And it's bloody absurd. Chrome is now No. 1. And they knew that long before StatCounter had anything to say about it. I won't say "let's face the facts and say FB has a bone to pick with Apple/Google." But please don't go the opposite end of the extreme to argue that, "Oh, no, this page doesn't mean anything. Obviously FB supports [JUST ABOUT EVERY OTHER BROWSER NOT ON THAT LIST.]"
I mean, c'mon... By this reason, FB supports Netscape 2, Firefox 3, Camino, Lynx, etc. etc etc.