Everyone has the same buttons; the view is personal

The host's rights and the co-host are gone: anyone in a session may
start a new page, put an image on the page, load a kept page, hide,
expand and shrink, and move or remove images and Hides; the page left
is kept in every notebook.  Fit and Normal scale act on your own screen
only.  A session goes on without whoever started it, and a newcomer to
an empty room starts page 1 with New.

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

client/index.html

@@ -82,12 +82,12 @@
     </div>
     </div>
     <div class="group after_settings" role="radiogroup" aria-label="Hide, Arrange and Eraser">
-      <button type="button" data-tool="hide" aria-pressed="false" hidden
+      <button type="button" data-tool="hide" aria-pressed="false"
               data-help="Hide part of the page for everyone: drag open a rectangle, and what lies under it is covered in white, marked by blue corners. Rest the pen on it to move it, or near a corner to resize it, or use Arrange; a tap of the eraser removes it.">Hide</button>
       <button type="button" data-tool="arrange" aria-pressed="false"
               data-help="Move and resize: the corners of every image are marked in blue, as those of Hides and text rectangles always are. Drag inside an image, a Hide or a text rectangle of yours to move it, drag a corner to resize it (an image keeps its shape). A press elsewhere does nothing. With any other tool, resting the pen on one of them for half a second does the same.">Arrange</button>
       <button type="button" data-tool="eraser" aria-pressed="false"
-              data-help="Erase your own strokes and text by moving over them. A tap on an image, or on a Hide rectangle, removes it, if you are the host or a co-host (or added the image yourself). Two quick taps on empty paper, away from anything the eraser would remove, undo your latest mark; again, and the one before.">Eraser</button>
+              data-help="Erase your own strokes and text by moving over them. A tap on an image, or on a Hide rectangle, removes it for everyone. Two quick taps on empty paper, away from anything the eraser would remove, undo your latest mark; again, and the one before.">Eraser</button>
     </div>
       <button id="undo" type="button" disabled
               data-help="Take back your latest mark: a stroke, an erasure, a text block typed or moved, a Hide rectangle. Again for the one before. Also Ctrl+Z (Command+Z on a Mac), or two quick taps of the eraser on empty paper. Only your own marks, and only on this page since you opened it.">Undo</button>
@@ -99,14 +99,14 @@
       <div id="page_menu" class="popup menu" role="menu" hidden>
         <div class="menu_title">Change the display of the page</div>
         <button id="zoom_fit" type="button" class="menu_item" role="menuitem"
-                data-help="Show the whole page in the window. Pressed by the host, it does so on every screen. Ctrl (Command on a Mac) with the scroll wheel, or with a pen stroke up or down, zooms about the pointer.">Fit to the window</button>
+                data-help="Show the whole page in the window, on your screen only. Ctrl (Command on a Mac) with the scroll wheel, or with a pen stroke up or down, zooms about the pointer.">Fit to the window</button>
         <button id="zoom_sheet" type="button" class="menu_item" role="menuitem"
-                data-help="Show the page at the scale a new page has, one full page filling the window. A shrunk page is then seen at its own size rather than enlarged. Pressed by the host, it does so on every screen.">Normal scale</button>
+                data-help="Show the page at the scale a new page has, one full page filling the window. A shrunk page is then seen at its own size rather than enlarged. On your screen only.">Normal scale</button>
         <hr>
         <div class="menu_title">Change the size of the page</div>
-        <button id="zoom_expand" type="button" class="menu_item" role="menuitem" hidden
+        <button id="zoom_expand" type="button" class="menu_item" role="menuitem"
                 data-help="Make the page fill the window, for everyone, at this zoom, in both directions. Nothing on it moves.">Expand to the window</button>
-        <button id="zoom_shrink" type="button" class="menu_item" role="menuitem" hidden
+        <button id="zoom_shrink" type="button" class="menu_item" role="menuitem"
                 data-help="Make the page, for everyone, just large enough for what is on it, with the margin around. Nothing on it moves.">Shrink to the contents</button>
         <hr>
         <label class="menu_item toggle" role="menuitemcheckbox"
@@ -119,7 +119,7 @@
       <button id="load_image" type="button"
               data-help="Put an image file, such as a scanned exercise, on the page for everyone: below the images already there, centred, at its own size. Rest the pen on an image to move it, or near a corner to scale it; it comes to the front. A tap of the eraser on an image removes it; writing on it stays.">Image</button>
       <button id="load_notebook_page" type="button"
-              data-help="Your notebooks and the pages kept in them, to look at or to delete. The host and co-hosts can start a new page for everyone from a kept page, with everything on it; the current page is then kept in each notebook.">Notebooks</button>
+              data-help="Your notebooks and the pages kept in them, to look at or to delete. A kept page starts a new page for everyone, with everything on it; the current page is then kept in each notebook.">Notebooks</button>
     </div>
     <div class="group" aria-label="Notebook">
       <select id="session_notebook" class="notebook_pick" aria-label="Current notebook"