View thread as single page

To some extent, this can be used in place of search functionality (view as a single page, then find on page). This is part of the extension. It's a feature I use often.

/includes/forums/thread.class.php could take an optional page length.

PAGINATE_PER_PAGE is currently a constant - really, we'd just be changing it to a variable.

What will the performance impact be? Without this feature users click many pages trying to find the content that they want - a single page view might improve performance because it would stop the users doing this.

Implementation? Dunno. A page size thing in the footer, with an "all" option?

I think all would be a problem for large threads. We do have threads with hundreds of posts in them, and as you've seen, there's no caching in v1 (it's built into v2). That said, with the indexes, it shouldn't be too bad, and I don't see this being used by everyone. Instead of at the bottom, I think it'd make sense to have this as a user option.