Also the new (old?) behaviour keeps the last tab open when I close the browser, which is annoying and a step backwards in usability. It doesn't seem to be possible to change this.
In my opinion it would have been better to leave the functionality and just turn it off by default.
That doesn't make it OK to remove a feature that people did use and like.
That feels like a bit of a slap - what if they decide to remove some other feature I like but other people don't use (e.g. the always allow zoom feature which I would not like to go without)