The chooser's marks are × at the left, tappable once marked

From the development repository at 5252a58.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/guest.md

@@ -304,7 +304,7 @@ right of your toolbar:
   your notebooks, with everything that was written on it.  A chooser
   shows your notebooks and small pictures of their kept pages.  The kept
   page itself is not changed: the session works on a copy.  The same
-  chooser deletes pages and notebooks of yours, marked with the dot at
+  chooser deletes pages and notebooks of yours, marked with the × at
   their left and then the **Delete** button, pressed twice; the host's part says
   more.
 * **Hide**, among the tools, hides part of the page for everyone: drag

docs/host.md

@@ -248,7 +248,7 @@ A lesson might go: **New**, **Image** for the exercise, work, **New**
 for a point of grammar, work, **Notebooks** to return to the exercise.
 
 The same chooser deletes.  Every page card and every notebook in the
-list carries a small dot at its left; a tap marks it with a tick, a second tap unmarks it,
+list carries a small × at its left; a tap marks it with a tick, a second tap unmarks it,
 and a marked notebook goes with every page in it.  As soon as something
 is marked, a **Delete** button in the chooser's header says how much:
 "Delete 3 pages?", "Delete 1 notebook and 3 pages?".  The first press