diff --git a/tests/web/web-host.test.ts b/tests/web/web-host.test.ts
index d80df4fa..d34af5f8 100644
--- a/tests/web/web-host.test.ts
+++ b/tests/web/web-host.test.ts
@@ -192,6 +192,10 @@ test("serves workspaces through a runtime isolated from terminal sessions", asyn
       /\.landing \.composer-dock \{[\s\S]*?align-self: center;/,
     );
     assert.match(stylesSource, /\.workbench-header \{\s*display: none;\s*\}/);
+    assert.match(
+      stylesSource,
+      /@media \(max-width: 760px\) \{\s*\.workbench-header \{[^}]*backdrop-filter: none;[^}]*-webkit-backdrop-filter: none;/,
+    );
     assert.match(
       stylesSource,
       /\.composer\.dormant \{[^}]*border-style: dashed/,
diff --git a/web/ui/styles.css b/web/ui/styles.css
index 0270ed9a..845eaff3 100644
--- a/web/ui/styles.css
+++ b/web/ui/styles.css
@@ -567,6 +567,8 @@ body.sidebar-collapsed .icon-button { width: 36px; height: 36px; }
     padding: 0;
     border: 0;
     background: transparent;
+    backdrop-filter: none;
+    -webkit-backdrop-filter: none;
     pointer-events: none;
   }
   .workbench-header .session-header,