the option to open a private tab as a normal tab is GONE. This is how I use Firefox: someone sends me a link, I click on it and it opens in a private tab by default. If I need to sign in to see it (e.g. private Instagram links) then I open it in a normal tab. This option is now simply gone.
I'm going to wager this is such a hyper-niche use case that the devs might genuinely not be aware of anybody doing this at all. Reminds me of the relevant XKCD, basically.