Fixes

assets/templates/base.njk

@@ -105,6 +105,7 @@
 {% block content %}{% endblock %}
     </div>
   </div>
+  {% include "version.njk" %}
 </main>
 
 {# Chrome, so it is written once here instead of built in JavaScript on every

assets/templates/reference.njk

@@ -44,12 +44,20 @@
 
    settled is what stops the load trigger looping: the answer to it is a
    picker already standing in the right place, and it says so by leaving the
-   trigger out of the copy it sends back. #}
+   trigger out of the copy it sends back.
+
+   !!location.hash, and not location.hash, because htmx keeps an event only
+   when the filter returns boolean true exactly -- it tests the result with
+   !== true -- and a hash is a string. Written without the coercion the
+   trigger is dead: every link carrying an anchor lands with the picker still
+   reading 1:1, which is where the worker rendered it, because a browser
+   keeps the fragment to itself and the request that would correct it is
+   never sent. #}
 <div class="reference navbar-text {% if reference %}d-flex{% else %}d-none{% endif %} align-items-center gap-1 ms-3"
      id="reference"
      {%- if oob %} hx-swap-oob="true"{% endif %}
      hx-get="api/reference"
-     hx-trigger="{% if reference and not settled %}load[location.hash], {% endif %}worker-ready from:body, htmx:historyRestore from:body"
+     hx-trigger="{% if reference and not settled %}load[!!location.hash], {% endif %}worker-ready from:body, htmx:historyRestore from:body"
      hx-target="this" hx-swap="outerHTML">
 {%- if reference %}
   <span class="reference-book text-light fw-semibold"

assets/templates/version.njk

@@ -0,0 +1,39 @@
+{# The footer under the book list: what this device is running, and the one
+   button that makes it forget.
+
+   Both digests are stamped into sw.js by server.py from the files on disk:
+   shell covers assets/, the hand-written chrome, and library covers bible/,
+   the generated pages. They are the same two values the worker names its
+   caches after, so a device showing a digest is a device serving that cache.
+
+   It says what the worker that composed this document was, not what is
+   controlling right now. An update installs, claims and starts answering
+   without this document being rebuilt, so the value only becomes current on
+   the next full load -- which is the reload you would do to check it anyway.
+
+   version is null in one case: boot.html composed this page, so there was no
+   worker to ask. The line is then absent, which is the honest answer -- no
+   worker means no version, and the bookmark slot in the navbar is empty for
+   the same reason. The button stays, because a device with no worker and a
+   full cache is exactly the state worth clearing.
+
+   Rendered on every page and shown under the book list alone. Populating it
+   only for the index would look like the smaller change and would not work:
+   the shell is composed once per full navigation, and a boosted link to the
+   book list swaps #content without rebuilding anything around it. So the page
+   decides, not the composer -- app.js looks for the index in #content after
+   every swap. The body class this was rendered with cannot be asked, for the
+   same reason: it goes stale the moment a link is clicked.
+
+   The button is a plain <button> outside any form, which is the whole of why
+   hx-boost on <body> leaves it alone: htmx boosts links, forms, and submits
+   belonging to one. resetApp() in js/app.js is what it runs. #}
+<div class="app-version d-none text-center mt-5 mb-2" id="app-version">
+{%- if version %}
+  <p class="app-version-digests form-text mt-0 mb-2">
+    shell {{ version.shell }} &middot; library {{ version.library }}
+  </p>
+{%- endif %}
+  <button type="button" class="app-reset btn btn-outline-secondary btn-sm"
+          id="app-reset">Reset app</button>
+</div>