diff --git a/playground/package-lock.json b/playground/package-lock.json
index f25650f3f0b446..0f1af5d971b121 100644
--- a/playground/package-lock.json
+++ b/playground/package-lock.json
@@ -41,10 +41,10 @@
         "pyodide": "^0.27.4",
         "react": "^19.0.0",
         "react-dom": "^19.0.0",
-        "react-resizable-panels": "^2.1.8",
+        "react-resizable-panels": "^2.1.7",
         "red_knot_wasm": "file:red_knot_wasm",
         "shared": "0.0.0",
-        "smol-toml": "^1.3.3"
+        "smol-toml": "^1.3.1"
       },
       "devDependencies": {
         "vite-plugin-static-copy": "^2.3.0"
@@ -6087,14 +6087,14 @@
         "monaco-editor": "^0.52.0",
         "react": "^19.0.0",
         "react-dom": "^19.0.0",
-        "react-resizable-panels": "^2.1.8",
+        "react-resizable-panels": "^2.0.0",
         "ruff_wasm": "file:ruff_wasm",
         "shared": "0.0.0",
-        "smol-toml": "^1.3.3"
+        "smol-toml": "^1.3.0"
       }
     },
     "ruff/ruff_wasm": {
-      "version": "0.11.3",
+      "version": "0.11.4",
       "license": "MIT"
     },
     "shared": {
@@ -6103,7 +6103,7 @@
         "@monaco-editor/react": "^4.7.0",
         "classnames": "^2.3.2",
         "react": "^19.0.0",
-        "react-resizable-panels": "^2.1.8"
+        "react-resizable-panels": "^2.1.7"
       }
     }
   }
diff --git a/playground/ruff/src/Editor/Diagnostics.tsx b/playground/ruff/src/Editor/Diagnostics.tsx
index 781c919205543c..427e5b24b2ccd9 100644
--- a/playground/ruff/src/Editor/Diagnostics.tsx
+++ b/playground/ruff/src/Editor/Diagnostics.tsx
@@ -66,27 +66,28 @@ function Items({
     );
   }
 
+  const uniqueIds: Map<string, number> = new Map();
+
   return (
     <ul className="space-y-0.5 grow overflow-y-scroll">
-      {diagnostics.map((diagnostic, index) => {
+      {diagnostics.map((diagnostic) => {
+        const row = diagnostic.start_location.row;
+        const column = diagnostic.start_location.column;
+        const mostlyUniqueId = `${row}:${column}-${diagnostic.code}`;
+
+        const disambiguator = uniqueIds.get(mostlyUniqueId) ?? 0;
+        uniqueIds.set(mostlyUniqueId, disambiguator + 1);
+
         return (
-          <li
-            key={`${diagnostic.start_location.row}:${diagnostic.start_location.column}-${diagnostic.code ?? index}`}
-          >
+          <li key={`${mostlyUniqueId}-${disambiguator}`}>
             <button
-              onClick={() =>
-                onGoTo(
-                  diagnostic.start_location.row,
-                  diagnostic.start_location.column,
-                )
-              }
+              onClick={() => onGoTo(row, column)}
               className="w-full text-start cursor-pointer select-text"
             >
               {diagnostic.message}{" "}
               <span className="text-gray-500">
-                {diagnostic.code != null && `(${diagnostic.code})`} [Ln{" "}
-                {diagnostic.start_location.row}, Col{" "}
-                {diagnostic.start_location.column}]
+                {diagnostic.code != null && `(${diagnostic.code})`} [Ln {row},
+                Col {column}]
               </span>
             </button>
           </li>