The "/forumthread" page:

Show all forum messages associated with a particular message thread. The result is basically the same as /forumpost except that none of the postings in the thread are selected.

Query parameters:

name=X

REQUIRED. The hash of any post of the thread.

t=a

Automatic display mode, i.e. hierarchical for desktop and chronological for mobile. This is the default if the "t" query parameter is omitted.

t=c

Show posts in the order they were written.

t=h

Show posts using hierarchical indenting.

unf

Show the original, unformatted source text.

hist

Show edit history in addition to current posts.