diff --git a/.changeset/fix-plugin-admin-pages.md b/.changeset/fix-plugin-admin-pages.md
new file mode 100644
index 000000000..8d90e24a9
--- /dev/null
+++ b/.changeset/fix-plugin-admin-pages.md
@@ -0,0 +1,5 @@
+---
+"emdash": patch
+---
+
+Fix: default adminPages and dashboardWidgets to empty arrays in manifest to prevent admin UI crash when plugins omit these properties.
diff --git a/packages/core/src/emdash-runtime.ts b/packages/core/src/emdash-runtime.ts
index c20d6d312..f37def639 100644
--- a/packages/core/src/emdash-runtime.ts
+++ b/packages/core/src/emdash-runtime.ts
@@ -1244,8 +1244,8 @@ export class EmDashRuntime {
 				version: plugin.version,
 				enabled,
 				adminMode,
-				adminPages: plugin.admin?.pages,
-				dashboardWidgets: plugin.admin?.widgets,
+				adminPages: plugin.admin?.pages ?? [],
+				dashboardWidgets: plugin.admin?.widgets ?? [],
 				portableTextBlocks: plugin.admin?.portableTextBlocks,
 				fieldWidgets: plugin.admin?.fieldWidgets,
 			};
@@ -1267,8 +1267,8 @@ export class EmDashRuntime {
 				enabled,
 				sandboxed: true,
 				adminMode: hasAdminPages || hasWidgets ? "blocks" : "none",
-				adminPages: entry.adminPages,
-				dashboardWidgets: entry.adminWidgets,
+				adminPages: entry.adminPages ?? [],
+				dashboardWidgets: entry.adminWidgets ?? [],
 			};
 		}
 
@@ -1290,8 +1290,8 @@ export class EmDashRuntime {
 				enabled,
 				sandboxed: true,
 				adminMode: hasAdminPages || hasWidgets ? "blocks" : "none",
-				adminPages: pages,
-				dashboardWidgets: widgets,
+				adminPages: pages ?? [],
+				dashboardWidgets: widgets ?? [],
 			};
 		}