For some reason, Apple's Web site where you can manage your Apple ID (appleid.apple.com) may block users of Linux browsers from accessing it. Having access to the site is important for managing things such as payment information, two-factor authentication, and other account information. Although the number of Linux users accessing the site must be relatively small compared to other operating systems, some iPhone users using Linux on the desktop see the problem.
Update: It seems that the problem has been resolved. 19659003] This behavior was first explained by the user Alexander Martin at Mastodon and then shared by Hacker News. He discovered that when the browser reports itself as a Linux browser, Apple's website blocks access by throwing a "Bad Gateway" error.
We could render the problem using the developer tools on Safari running on Mac, if the webpage meets the string "Linux" in the user agent, the connection is interrupted by the "Bad Gateway" error message.
It's unclear whether this was a deliberate decision from Apple, or if it's just a mistake on their website. It is possible that the site for security purposes only accepts a set of whitelisted user agents, and that the relatively small amount of Linux users accessing the site was forgotten about the operating system.
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