I've always had the view where the entire thread is shown on one page (so OP's post are highlighted and you can scroll through the whole thread, up to 999 posts, on one page).
This has suddenly changed and it's asking me to click through each page, or each time I open a thread I have to click on the 'see 1000 messages' option, which I keep forgetting to do, so only see part of the thread.
It's driving me mad - how do I get the default setting back?