Intermittent network failures on self-hosted instance cause token renewal failure and session logout

https://sonarly.com/issue/13837?type=bug

Intermittent `TypeError: Failed to fetch` errors on POST to `https://vedio.twenty.com/metadata` cause the token renewal flow to fail, logging the user out and redirecting to `/welcome`.

packages/twenty-front/src/modules/error-handler/components/PromiseRejectionEffect.tsx

@@ -27,10 +27,22 @@ export const PromiseRejectionEffect = () => {
         error.networkError?.name === 'AbortError' ||
         error.name === 'AbortError';
 
-      if (!isAbortError) {
+      // Transient network errors (Failed to fetch, Load failed) from Apollo
+      // are not actionable — typically caused by unstable connectivity or
+      // browser tab backgrounding. Skip both the snackbar and Sentry.
+      const isTransientNetworkError =
+        error.name === 'ApolloError' &&
+        isEmpty(error.graphQLErrors) &&
+        error.networkError?.name === 'TypeError';
+
+      if (!isAbortError && !isTransientNetworkError) {
         enqueueErrorSnackBar({});
       }
 
+      if (isTransientNetworkError) {
+        return;
+      }
+
       try {
         const { captureException } = await import('@sentry/react');
         captureException(error, (scope) => {

packages/twenty-front/src/modules/error-handler/components/SentryInitEffect.tsx

@@ -54,6 +54,14 @@ export const SentryInitEffect = () => {
             tracesSampleRate: 1.0,
             replaysSessionSampleRate: 0.1,
             replaysOnErrorSampleRate: 1.0,
+            ignoreErrors: [
+              // Transient network errors from Apollo — not actionable,
+              // typically caused by unstable connectivity on self-hosted
+              // instances or browser tab backgrounding.
+              'Failed to fetch',
+              'NetworkError when attempting to fetch resource',
+              'Load failed',
+            ],
           });
 
           setIsSentryInitialized(true);