Most browsers have what they call a privacy or incognito mode. The idea is that it deletes any cookies and cache created by a website you ventured into once you close the browser (important step here). Note it does not replace a VPN or anonymize your traffic in any way; there are other tools for that. Still, I not only like that but I set my browsers to always start in that mode (we can talk about how to do so in a future post). Cookies is one of the ways websites use to track you (as in what GDPR would consider to be personal data), your habits, so they can know more about you than you do. I would rather not they do that. Also, shadier individuals -- even shadier than certain commercial organizations that I rather not mention -- also like them when they gain access (think phishing attacks) to your system as these files may have fun stuff like session cookies and even passwords they can steal.
Understandly, some companies do not like when I get rid of their cookies, but it is hard for them to do a thing because this is done at the user's end. However, it seems T-Mobile found a way around that: they chose to detect and block the user of Firefox running in Incognito Mode in their website:
Even though I provided the link to the official page, here is the text for those who are using a text based browser or cannot see images:
Firefox is no longer supported in private mode The Firefox browser is no longer supported in private mode on our site. To continue, please take Firefox out of private mode or choose another browser. We recommend Chrome, Safari or Edge.
Why are they singling out Firefox and derivatives (I also tried LibreWolf before writing this article)?
- Could it be they assume everyone either uses a Windows, a Mac computer, or at least a Google-derives ystem (think Chromebook and Android), and any user running neither (I use Linux) is to be treated with mistrust?
- Could it be that Safari stopped supporting extensions such as UBlock Origin, and Edge, well, is Edge just like the normal (as in not ungoogled) version of Chrome talks too much back to the mothership? After all, these browsers do have their versions of privacy modes, so that can't be the main issue. Nor that most sites, banks included, seem to work just fine with Firefox incognito mode.
Contacting T-Mobile led to nothing, so all I have are the speculations I made here. You too can make your own!