Yeah I can do each page individually, via my own browser print function, but it would be more convenient to have a "print/show as one page" button to click on. I tried your "/all" trick and it didn't work for me either.
On the old board software, you could put ' /all ' at the end of the thread and it would print to PDF (using appropriate PDF tool) as one super long thread. I just tried that here with the new software, but can't get it to show all pages as one long thread in print mode. I can PDF print each page though.