diff --git a/packages/domain/src/plugin-sdk-version.ts b/packages/domain/src/plugin-sdk-version.ts
index 232bbe94ac..cd0a914b39 100644
--- a/packages/domain/src/plugin-sdk-version.ts
+++ b/packages/domain/src/plugin-sdk-version.ts
@@ -16,7 +16,7 @@
 // PLUGIN_SDK_MAJOR is 0, so the major-only artifact gate cannot distinguish
 // 0.x releases and is intentionally vacuous for them until a future 1.0.
 // Rebuildable artifacts still rebuild on the exact sdkVersion-differs trigger.
-export const PLUGIN_SDK_VERSION = "0.4.22";
+export const PLUGIN_SDK_VERSION = "0.4.23";
 
 /** Major of {@link PLUGIN_SDK_VERSION} — the plugin API compatibility number. */
 export const PLUGIN_SDK_MAJOR = Number(PLUGIN_SDK_VERSION.split(".", 1)[0]);
diff --git a/packages/plugin-api-map/sdk-public-api.json b/packages/plugin-api-map/sdk-public-api.json
index 12722bee24..a506cd20af 100644
--- a/packages/plugin-api-map/sdk-public-api.json
+++ b/packages/plugin-api-map/sdk-public-api.json
@@ -27,7 +27,7 @@
     },
     "./provider-bridge/testing": {
       "types": "bundled-types/bb-plugin-sdk-provider-bridge-testing.d.ts",
-      "sha256": "7c97c6976876e450ecc9dab36314a48215aae11054e410f985433cd322f9cde8"
+      "sha256": "c35f7c70cdde2281a6fc5b51a041ea9281f4c232d6a4d730a823cbd5ef8aa8a9"
     },
     "./testing": {
       "types": "bundled-types/bb-plugin-sdk-testing.d.ts",
diff --git a/packages/plugin-sdk/package.json b/packages/plugin-sdk/package.json
index ba46313380..f7d2089651 100644
--- a/packages/plugin-sdk/package.json
+++ b/packages/plugin-sdk/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@get-bb/plugin-sdk",
-  "version": "0.4.22",
+  "version": "0.4.23",
   "homepage": "https://github.com/get-bb/bb#readme",
   "bugs": {
     "url": "https://github.com/get-bb/bb/issues"
diff --git a/plugins/workflows/src/app.test.tsx b/plugins/workflows/src/app.test.tsx
index 6ff44de568..5b1e99c383 100644
--- a/plugins/workflows/src/app.test.tsx
+++ b/plugins/workflows/src/app.test.tsx
@@ -685,6 +685,11 @@ describe("workflow thread panel", () => {
     );
 
     await slot.findByText("Run independent checks before shipping.");
+    const scrollArea = slot.container.querySelector(
+      '[data-detail-scroll-area="workflow-panel"]',
+    );
+    expect(scrollArea?.className).toContain("p-4");
+    expect(scrollArea?.parentElement?.className).toContain("bg-border");
     // The settled Discover phase starts collapsed; the active phase is open.
     expect(slot.queryByText("Inspect implementation")).toBeNull();
     expect(slot.getByText("Adversarial review")).toBeTruthy();
diff --git a/plugins/workflows/src/app.tsx b/plugins/workflows/src/app.tsx
index 5dff85e37a..3bb21a3e7b 100644
--- a/plugins/workflows/src/app.tsx
+++ b/plugins/workflows/src/app.tsx
@@ -861,11 +861,13 @@ function WorkflowPreviewLoaded({
 function WorkflowRunPanel({ threadId, params }: PluginThreadPanelProps) {
   const runId = panelRunId(params);
   return (
-    <div className="h-full min-h-0 flex-1 p-4">
+    <div className="h-full min-h-0 flex-1 bg-border">
       {runId === undefined ? (
-        <EmptyOrError>
-          This workflow panel has invalid run parameters.
-        </EmptyOrError>
+        <div className="p-4">
+          <EmptyOrError>
+            This workflow panel has invalid run parameters.
+          </EmptyOrError>
+        </div>
       ) : (
         <WorkflowRunPanelLoaded threadId={threadId} runId={runId} />
       )}
@@ -921,10 +923,10 @@ function WorkflowRunPanelLoaded({
     }
   };
   return (
-    <div className="flex h-full min-h-0 flex-col bg-background">
+    <div className="flex h-full min-h-0 flex-col bg-border">
       <div
         data-detail-scroll-area="workflow-panel"
-        className="min-h-0 flex-1 overflow-y-auto"
+        className="min-h-0 flex-1 overflow-y-auto p-4"
       >
         <div className="flex items-start gap-2">
           <div className="min-w-0 flex-1">