reCAPTCHA is a rate-limiting measure. Google handles all the heavy-lifting and attacker protection for you, and the slow fade you see in the video is that rate-limiting in action. But if you get a clean CAPTCHA result back from them, then that client is very unlikely to be an automated attacker. It's super easy and scales really well.
Conveniently, normal users with typical browser configurations get nothing but the animated checkbox. For nearly everyone, the whole experience is simple and easy. The only people who get inconvenienced are the low-grade privacy enthusiasts who think that preventing tracking is the path to Internet safety. Ironically, "tracking" is literally the mechanism by which legitimate users can be distinguished from attackers, so down that road lies a sort of self-inflicted hell for which the only sensible solution is to stop hitting yourself.
It's not Firefox that's the problem; reCAPTCHA works just fine on Firefox. It's all those anti-tracking measures you installed and enabled -- they work by making your browser indistinguishable from a low-quality bot, kicking the website into self-defense mode. The slow fade is a rate-limiting measure. It's annoying to you, but it's more annoying to people trying to automate login attempts.
The site is attempting to protect your account by preventing automated attacks against it. Meanwhile your browser is doing it's best to look like a shell script, refusing to send any sort of behavioral feedback or distinguishing characteristics that might give away the fact that you're a human.
So the question is: is it really worth alienating those quirky, paranoid users who take extraordinary anti-tracking measures, just to protect your normal users from automated attacks?
Thing is, Blink is not Chromium, Chromium is not Chrome, neither of them is Google, and BSD-3-clause is a pretty damn solid bulwark against the monopolization of the "control of fundamental online infrastructure", were that to ever become a concern again.
And the other bit is that the building blocks that make up Chromium power a lot of technology that is totally independent of anything under Google's influence, including NodeJS, Cloudflare's Workers, Microsoft's VS Code, and Amazon's Firecracker. They use it because it's solid, well-engineered tech. And even though Google wrote it, Google can't control it or stop you from using it against them. Microsoft isn't ceding anything at all to Google, Google's not in control of anything here.
The uncomfortable truth is that the role of neither Gecko nor Firefox nor Mozilla is particularly critical in terms of protecting the free and open Internet. What prevents Google from going all IE6 with Chrome isn't Mozilla, it's Chromium. If IE had been a BSD-licensed open-source project since 1995, then all the BS we endured in 2002 could never have happened; explorerium would have been trivially forked to create a sensible competitor with no switching cost.
Google tied their own hands from the very beginning, and by ensuring Chromium doesn't lag behind, they're keeping their hands tied. Almost as if they were doing it on purpose. In fact, the fact that Microsoft is switching to Chromium locks both tech giants into an intriguing sort of bargain. Each can benefit from the other's work as long as neither strays too far from the open source codebase, as long as they both push their changes into the open. So you end up with a reasonable guarantee that the future of the Internet stays independent; not because of a nonprofit competitor with a strongly-worded manifesto, but because none of the the main players can afford to make it closed.
I dug into the details earlier this year, and it turned out at the time that Microsoft counts some undisclosed but significant percentage of revenue from sales of Office 365 in their "Commercial Cloud" category, even if you buy it in a box at a store... because in theory that box entitles you to Office In the Cloud. This (Azure plus some percentage of Office) is the "Azure" revenue number that gets compared to AWS and GCP to determine the market share number that you see in all the graphs.
Can anyone confirm/deny? I'm reasonably certain this is right from my reading of financial reports, but I'm no accountant.
Conveniently, normal users with typical browser configurations get nothing but the animated checkbox. For nearly everyone, the whole experience is simple and easy. The only people who get inconvenienced are the low-grade privacy enthusiasts who think that preventing tracking is the path to Internet safety. Ironically, "tracking" is literally the mechanism by which legitimate users can be distinguished from attackers, so down that road lies a sort of self-inflicted hell for which the only sensible solution is to stop hitting yourself.