diff --git a/modules/app.xqm b/modules/app.xqm
index af8532484..124ad58b1 100644
--- a/modules/app.xqm
+++ b/modules/app.xqm
@@ -134,6 +134,11 @@ declare
                 let $subsubFacets := $coll => ft:facets("chronology", (), ($label,$subLabel))
                 return
                     <xhtml:li>
+                        {
+                            if(($label,$subLabel) => string-join() = $activeLabelString)
+                            then attribute class {'active'}
+                            else ()
+                        }
                         <xhtml:span class="datefacet toggle-toc-item">
                             {
                             if (map:size($subsubFacets) gt 0)
@@ -143,10 +148,7 @@ declare
                             )
                             else()
                             }
-                            <xhtml:span class="label{
-                                if(($label,$subLabel) => string-join() = $activeLabelString)
-                                then ' active'
-                                else ()}" data-value="{($label,$subLabel) => string-join(',')}">{$subLabel}</xhtml:span>
+                            <xhtml:span class="label" data-value="{($label,$subLabel) => string-join(',')}">{$subLabel}</xhtml:span>
                             <xhtml:span class="count">{$count}</xhtml:span>
                         </xhtml:span>
                         {
diff --git a/resources/js/init.js b/resources/js/init.js
index 660cd3b7f..0d559cdd4 100644
--- a/resources/js/init.js
+++ b/resources/js/init.js
@@ -296,12 +296,17 @@ $('body').on('click touchstart', function (e) {
  * hide/reveal sub items of the table of contents of the Guidelines and Wikipedia
  */
 $('.toggle-toc-item')
-    .on('click', toggleTocItems)
-    .each(toggleTocItems);
+    .on('click', toggleTocItems) /* toggle on click */
+    .each(toggleTocItems); /* initially collapse all */
 $('.toc a[href~="'+window.location.pathname+window.location.hash+'"]').parentsUntil(".guidelines").addClass("active");
 $('.appendix a[href^="'+window.location.pathname+window.location.hash+'"]').parentsUntil(".appendix-div").addClass("active");
 $(".toc .active").siblings(".toggle-toc-item").each(toggleTocItems);
 
+/* initially open selected chronology facets */
+/* … along the ancestor axis */
+$('.datefacets li.active').parentsUntil('.datefacets', 'li').children('.toggle-toc-item').each(toggleTocItems);
+/* … and the (direct) child axis */
+$('.datefacets li.active').children('.toggle-toc-item').each(toggleTocItems);
 
 /*
  * used for Guidelines TOC as well as for Wikipedia
diff --git a/resources/sass/layout/_sidebar.scss b/resources/sass/layout/_sidebar.scss
index f5d64ecc4..a5daee8f8 100644
--- a/resources/sass/layout/_sidebar.scss
+++ b/resources/sass/layout/_sidebar.scss
@@ -143,6 +143,9 @@ a.checkbox-only {
             align-items: start;
             cursor: pointer;
             color: $primary;
+            &:has(.label.active) {
+                font-weight: 800;
+            }
             .label {
                 flex: 1;
             }