diff --git a/locales/en/app.json b/locales/en/app.json
index 5398930f..694873de 100644
--- a/locales/en/app.json
+++ b/locales/en/app.json
@@ -51,6 +51,7 @@
     "reactions": "Reactions",
     "reconnecting": "Reconnecting…",
     "settings": "Settings",
+    "technical_details": "Technical details",
     "unencrypted": "Not encrypted",
     "username": "Username",
     "video": "Video"
diff --git a/src/ErrorView.module.css b/src/ErrorView.module.css
index bd68f5e3..e37079ca 100644
--- a/src/ErrorView.module.css
+++ b/src/ErrorView.module.css
@@ -20,3 +20,21 @@
   color: var(--cpd-color-text-secondary);
   text-align: center;
 }
+
+.technicalDetails {
+  margin-top: var(--cpd-space-1x);
+}
+
+.technicalDetailsSummary {
+  cursor: pointer;
+  font-weight: bold;
+}
+
+.technicalDetailsPre {
+  margin-top: var(--cpd-space-2x);
+  padding: var(--cpd-space-2x);
+  background-color: var(--cpd-color-bg-subtle-secondary);
+  overflow: auto;
+  font-size: var(--cpd-font-size-body-sm);
+  white-space: pre-wrap;
+}
diff --git a/src/livekit/openIDSFU.ts b/src/livekit/openIDSFU.ts
index 2d6c45b6..00cf69b1 100644
--- a/src/livekit/openIDSFU.ts
+++ b/src/livekit/openIDSFU.ts
@@ -5,7 +5,11 @@ SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
 Please see LICENSE in the repository root for full details.
 */
 
-import { type IOpenIDToken, type MatrixClient } from "matrix-js-sdk";
+import {
+  type IOpenIDToken,
+  type MatrixClient,
+  parseErrorResponse,
+} from "matrix-js-sdk";
 import { type CallMembershipIdentityParts } from "matrix-js-sdk/lib/matrixrtc/EncryptionManager";
 import { type Logger } from "matrix-js-sdk/lib/logger";
 
@@ -248,7 +252,7 @@ async function getLiveKitJWT(
   });
 
   if (!res.ok) {
-    throw new Error("SFU Config fetch failed with status code " + res.status);
+    throw parseErrorResponse(res, await res.text());
   }
   return await res.json();
 }
@@ -308,7 +312,7 @@ export async function getLiveKitJWTWithDelayDelegation(
     if (res.status === 404) {
       throw new NotSupportedError(msg);
     } else {
-      throw new Error(msg);
+      throw parseErrorResponse(res, await res.text());
     }
   }
   return await res.json();
diff --git a/src/room/GroupCallErrorBoundary.test.tsx b/src/room/GroupCallErrorBoundary.test.tsx
index 86921710..5b619115 100644
--- a/src/room/GroupCallErrorBoundary.test.tsx
+++ b/src/room/GroupCallErrorBoundary.test.tsx
@@ -25,12 +25,14 @@ import {
   ConnectionLostError,
   E2EENotSupportedError,
   type ElementCallError,
+  FailToGetOpenIdToken,
   InsufficientCapacityError,
   MatrixRTCTransportMissingError,
   UnknownCallError,
 } from "../utils/errors.ts";
 import { mockConfig } from "../utils/test.ts";
 import { ElementWidgetActions, type WidgetHelpers } from "../widget.ts";
+import { MatrixError } from "matrix-js-sdk";
 
 test.each([
   {
@@ -252,3 +254,69 @@ test("should have a close button in widget mode", async () => {
   );
   expect(mockWidget.api.transport.stop).toHaveBeenCalled();
 });
+
+test("should show technical details when error has a matrixError cause", async () => {
+  const underlyingError = new MatrixError(
+    {
+      errcode: "M_LOOKUP_FAILED",
+      error: "Failed to look up user info from homeserver",
+    },
+    500,
+    "https://matrix-rtc.m.localhost/livekit/jwt/sfu/get",
+  );
+  const error = new FailToGetOpenIdToken(underlyingError);
+
+  const TestComponent = (): ReactNode => {
+    throw error;
+  };
+
+  render(
+    <BrowserRouter>
+      <GroupCallErrorBoundary
+        onError={vi.fn()}
+        recoveryActionHandler={vi.fn()}
+        widget={null}
+      >
+        <TestComponent />
+      </GroupCallErrorBoundary>
+    </BrowserRouter>,
+  );
+
+  await screen.findByText("Something went wrong");
+
+  // Technical details should be present
+  const detailsElement = screen.getByText("Technical details");
+  expect(detailsElement).toBeInTheDocument();
+
+  // Verify error details are shown
+  expect(
+    screen.getByText(/Failed to look up user info from homeserver/i, {
+      selector: "pre",
+    }),
+  ).toBeInTheDocument();
+});
+
+test("should not show technical details when error has no matrix error cause", async () => {
+  const error = new ConnectionLostError();
+
+  const TestComponent = (): ReactNode => {
+    throw error;
+  };
+
+  render(
+    <BrowserRouter>
+      <GroupCallErrorBoundary
+        onError={vi.fn()}
+        recoveryActionHandler={vi.fn()}
+        widget={null}
+      >
+        <TestComponent />
+      </GroupCallErrorBoundary>
+    </BrowserRouter>,
+  );
+
+  await screen.findByText("Connection lost");
+
+  // Technical details should not be present (ConnectionLostError has no cause)
+  expect(screen.queryByText("Technical details")).not.toBeInTheDocument();
+});
diff --git a/src/room/GroupCallErrorBoundary.tsx b/src/room/GroupCallErrorBoundary.tsx
index ca407ed4..f77c3359 100644
--- a/src/room/GroupCallErrorBoundary.tsx
+++ b/src/room/GroupCallErrorBoundary.tsx
@@ -34,6 +34,8 @@ import {
 import { FullScreenView } from "../FullScreenView.tsx";
 import { ErrorView } from "../ErrorView.tsx";
 import { type WidgetHelpers } from "../widget.ts";
+import styles from "../ErrorView.module.css";
+import { MatrixError } from "matrix-js-sdk";
 
 export type CallErrorRecoveryAction = "reconnect"; // | "retry" ;
 
@@ -78,6 +80,9 @@ const ErrorPage: FC<ErrorPageProps> = ({
     });
   }
 
+  const technicalError =
+    error.cause instanceof MatrixError ? error.cause : null;
+
   return (
     <FullScreenView>
       <ErrorView
@@ -95,6 +100,16 @@ const ErrorPage: FC<ErrorPageProps> = ({
             />
           )}
         </p>
+        {technicalError ? (
+          <details className={styles.technicalDetails}>
+            <summary className={styles.technicalDetailsSummary}>
+              Technical details
+            </summary>
+            <pre className={styles.technicalDetailsPre}>
+              {technicalError.message}
+            </pre>
+          </details>
+        ) : null}
         {actions &&
           actions.map((action, index) => (
             <Button