Is there an easy way to switch between threaded vs linear view for a thread?

Sometime the context of a response is unclear when viewing in linear format and I’d like to know which message the response was actually made to. If there was an easy way to get to the original message, via a link or other mechanism, that would solve my problem as well but right now it seems that I have to switch to threaded view in preferences in order to determine what message a response was made for. It might be nice to have a “switch view” option on the thread drop down menu.