When the mailbox is sorted by threads, there are a few additional functions available in the index and pager modes.
D delete-thread delete all messages in the current thread ^U undelete-thread undelete all messages in the current thread ^N next-thread jump to the start of the next thread ^P previous-thread jump to the start of the previous thread ^R read-thread mark the current thread as read ESC d delete-subthread delete all messages in the current subthread ESC u undelete-subthread undelete all messages in the current subthread ESC n next-subthread jump to the start of the next subthread ESC p previous-subthread jump to the start of the previous subthread ESC r read-subthread mark the current subthread as read ESC t tag-thread toggle the tag on the current thread ESC v collapse-thread toggle collapse for the current thread ESC V collapse-all toggle collapse for all threads P parent-message jump to parent message in thread
Note: Collapsing a thread displays only the first message in the thread and hides the others. This is useful when threads contain so many messages that you can only see a handful of threads on the screen. See %M in $index_format. For example, you could use "%?M?(#%03M)&(%4l)?" in $index_format to optionally display the number of hidden messages if the thread is collapsed.
See also: $strict_threads.