Below the title of the thread for topics with more than one page there is a page icon followed by page numbers and the word all. If you click all you will see the posts all on the same page.
It took me a minute to find what you were talking about. I didn't realize you meant under the list of threads within a given forum. I thought you meant while already looking at a thread. Found it! Thanks. That will be helpful when looking for a particular quote.