As a relatively new user of zulip, I was surprised to find that the downward facing arrow beside streams in the left panel serves as a settings menu, rather than expanding the stream's topics. A more standard UI is to have a gear for settings, and an arrow to expand/collapse. At present, one must click the stream to view the topics contained therein, which has the side effect of narrowing the threads in the main viewport. It would be useful (to me) to be able to view threads without narrowing to the stream. One use case is cross-posting links across streams.