Sometimes with very long threads of multiple pages I save them for later viewing, can you still view all the posts on a single page? On the old version you could show a printable view then show all the posts on the one page.
On the top of each thread, there is a pull-down called thread tools. In there is a button for a printable view. You might try that.
No, with that you can still only display 50 posts at a time.
After all the bugs are ironed out, here’s another vote for bringing back the unlimited-posts-per-page printable view.