The question was not about bottom vs top, iiuc. It was about having the tabs always visible vs behind a tab button. As far as I can see, there is no way of doing that.
Not that I would want it, myself, since my current counter is 48 tabs and I don't want a bunch more hit regions when I'm thumb-browsing.
It appears I did miss a part of the question. My tab count is ∞ because I'm over 99 and tabs are unloaded. At that rate, if I were on a tablet or something, I'd prefer access to TreeStyleTabs or the like anyhow because horizontal becomes a squished mess. I assume the ctrl+tab as well as alt+{1-9} shortcuts still work.
Not that I would want it, myself, since my current counter is 48 tabs and I don't want a bunch more hit regions when I'm thumb-browsing.