help: Document "View user profile" mobile app feature.

Adds instructions for mobile app users.

static/styles/portico/markdown.css

@@ -241,12 +241,6 @@
             box-shadow: none;
             border: none;
         }
-
-        &.mobile-icon {
-            width: 24px;
-            box-shadow: none;
-            border: none;
-        }
     }
 
     .warn,

templates/zerver/help/view-someones-profile.md

@@ -18,8 +18,18 @@ streams for which [you can see all subscribers](/help/stream-permissions).
 
 !!! Tip ""
 
-    If you are viewing a list of messages, you can also click on a user's
+    You can also click on a user's profile picture or name on a
-    profile picture or name and skip to the last step.
+    message they sent, and skip to the last step.
+
+{tab|mobile}
+
+1. Tap on a user's profile picture or name.
+
+!!! Tip ""
+
+    If you are viewing a private message conversation, you can also tap the information
+    (<img src="/static/images/help/mobile-info-circle-icon.svg" alt="information" class="mobile-icon"/>)
+    button in the top right corner of the app.
 
 {end_tabs}