matrix: can I see who is in specific room without being there myself?

pages/matrix.markdown

@@ -31,6 +31,7 @@ links.*
 * [Why so many accounts?](#why-so-many-accounts)
 * [Why do you use Matrix URI scheme instead of matrix.to?](#why-do-you-use-matrix-uri-scheme-instead-of-matrixto)
 * [What are ghost and puppets?](#what-are-ghost-and-puppets)
+* [Can I see who is in any specific room without being there?](#can-i-see-who-is-in-any-specific-room-without-being-there)
 * [What does the public history visibility mean? I don’t want to appear in search engines](#what-does-the-public-history-visibility-mean-i-dont-want-to-appear-in-search-engines)
 * [What are state resets?](#what-are-state-resets)
   * [How about DAG splits?](#how-about-dag-splits)
@@ -96,6 +97,12 @@ from reading the future messages, Matrix will share keys to new joiners to
 some extent. For more information refer to [Matrix Spec issue #1](https://github.com/matrix-org/matrix-spec/issues/1)
 and related issues.
 
+### Can I see who is in any specific room without being there?
+
+In general no, although there is a cornercase that by poking room directory API e.g. for [Matrix Suomi](r/matrix.fi:matrix.org): [https://matrix-client.matrix.org/_matrix/client/v3/directory/room/%23matrix.fi%3Amatrix.org](https://matrix-client.matrix.org/_matrix/client/v3/directory/room/%23matrix.fi%3Amatrix.org), you get the room ID and list of homeservers in it and if you see a single user (or otherwise not so popular homeserver), you can make educated guesses on who may be in the room.
+
+I think this requires for the room to have an alias (not-published one should be fine) and a homeserver aware of the alias and room being queried.
+
 ### What are state resets?
 
 The term is used least in two different scenarios: