Stop hiding the top bar globally -- it hid the Save button on entity edit forms

.top-bar was unconditionally hidden on every page (admin_chrome library)
on the assumption it always renders empty, which held on our own pages
but not on entity edit forms, where Gin puts the page's local actions --
Save included -- inside .top-bar. Folded it into the same route-scoped
library as the admin sidebar (renamed hide_admin_sidebar ->
hide_admin_chrome) so both are hidden only on our front-end routes and
real admin pages keep a working Save button.

web/modules/custom/figli_compta_ledger/css/admin-chrome.css

@@ -1,23 +1,7 @@
-/* Core Navigation's top bar (`.top-bar`) only shows itself when its
-   tools/context/actions regions are non-empty -- but with no blocks placed
-   there, the regions still contain whitespace text nodes from the Twig
-   loop scaffolding, which defeats the `:not(:empty)` check. Result: an
-   empty top bar renders anyway, with the page content pushed down to make
-   room for it. We only use the Gin sidebar (the left icon rail), so force
-   the phantom bar off and collapse the space it would otherwise reserve. */
-.top-bar {
-  display: none !important;
-}
-
-.top-bar ~ .dialog-off-canvas-main-canvas {
-  margin-block-start: 0 !important;
-}
-
 /* Grand livre / Dashboard switcher, top-right of both pages. Only present
-   on those two custom routes, but attached here (already loaded on every
-   page for the phantom-top-bar fix above) rather than duplicated between
-   home.css and dashboard.css -- and defined with its own explicit colors
-   rather than relying on either page's #figli-*-app-scoped custom
+   on those two custom routes, but attached here rather than duplicated
+   between home.css and dashboard.css -- and defined with its own explicit
+   colors rather than relying on either page's #figli-*-app-scoped custom
    properties, since this <nav> sits outside both of those elements. */
 .figli-page-nav {
   display: flex;

web/modules/custom/figli_compta_ledger/css/hide-admin-chrome.css

@@ -0,0 +1,28 @@
+/* Only attached on this module's own front-end routes (see
+   figli_compta_ledger_page_attachments()) -- real Drupal admin pages
+   (/admin/*, node edit forms, etc.) keep all of this as normal.
+   Previously the top-bar rule below was unconditional (attached on every
+   page via admin_chrome), on the assumption that core Navigation's top
+   bar (`.top-bar`) always renders empty -- true on our own pages (no
+   blocks placed there, so whitespace text nodes from the Twig loop
+   scaffolding defeat its own `:not(:empty)` visibility check), but wrong
+   on entity edit forms, where Gin puts the page's local actions (the
+   Save button included) *inside* `.top-bar` -- hiding it there hid Save
+   itself, not just an empty bar. */
+.top-bar {
+  display: none !important;
+}
+.top-bar ~ .dialog-off-canvas-main-canvas {
+  margin-block-start: 0 !important;
+}
+
+/* The core Navigation module's admin sidebar (#admin-toolbar, ~65px fixed
+   rail) + its collapsed-state control bar and overlay. */
+#admin-toolbar,
+.admin-toolbar-control-bar,
+.admin-toolbar-overlay {
+  display: none !important;
+}
+.dialog-off-canvas-main-canvas {
+  margin-inline-start: 0 !important;
+}

web/modules/custom/figli_compta_ledger/css/hide-admin-sidebar.css

@@ -1,13 +0,0 @@
-/* The core Navigation module's admin sidebar (#admin-toolbar, ~65px fixed
-   rail) + its collapsed-state control bar and overlay. Only attached on
-   this module's own front-end routes (see
-   figli_compta_ledger_page_attachments()) -- real Drupal admin pages
-   (/admin/*, node edit forms, etc.) keep the sidebar as normal. */
-#admin-toolbar,
-.admin-toolbar-control-bar,
-.admin-toolbar-overlay {
-  display: none !important;
-}
-.dialog-off-canvas-main-canvas {
-  margin-inline-start: 0 !important;
-}

web/modules/custom/figli_compta_ledger/figli_compta_ledger.libraries.yml

@@ -34,7 +34,7 @@ admin_chrome:
   dependencies:
     - core/drupal
 
-hide_admin_sidebar:
+hide_admin_chrome:
   css:
     theme:
-      css/hide-admin-sidebar.css: {}
+      css/hide-admin-chrome.css: {}

web/modules/custom/figli_compta_ledger/figli_compta_ledger.module

@@ -219,14 +219,11 @@ function figli_compta_ledger_theme($existing, $type, $theme, $path) {
 /**
  * Implements hook_page_attachments().
  *
- * Core Navigation's top bar renders empty (whitespace-only regions defeat
- * its own :not(:empty) visibility check) on every page, not just admin
- * routes -- attach the fix globally rather than per-route.
- *
- * The admin sidebar itself (#admin-toolbar) is only hidden on this
- * module's own front-end pages -- real Drupal admin pages (/admin/*, node
- * edit forms, etc.) should keep it, so that one is route-scoped rather
- * than folded into the always-on admin_chrome attachment above.
+ * The admin top bar and sidebar (Gin/core Navigation chrome) are only
+ * hidden on this module's own front-end pages -- real Drupal admin pages
+ * (/admin/*, node edit forms, etc.) keep them, since Gin puts the page's
+ * local actions (Save included) inside the top bar there. Route-scoped
+ * rather than folded into the always-on admin_chrome attachment below.
  */
 function figli_compta_ledger_page_attachments(array &$attachments) {
   $attachments['#attached']['library'][] = 'figli_compta_ledger/admin_chrome';
@@ -238,7 +235,7 @@ function figli_compta_ledger_page_attachments(array &$attachments) {
     'figli_compta_ledger.link_entree',
   ];
   if (in_array(\Drupal::routeMatch()->getRouteName(), $front_end_routes, TRUE)) {
-    $attachments['#attached']['library'][] = 'figli_compta_ledger/hide_admin_sidebar';
+    $attachments['#attached']['library'][] = 'figli_compta_ledger/hide_admin_chrome';
   }
 }