diff --git a/app/javascript/mastodon/features/ui/containers/notifications_container.js b/app/javascript/mastodon/features/ui/containers/notifications_container.js
index 5924197f1e8c09ea2830511f312e19075057f87f..b60a0216f628e22ec047b572e104bba2a275c697 100644
--- a/app/javascript/mastodon/features/ui/containers/notifications_container.js
+++ b/app/javascript/mastodon/features/ui/containers/notifications_container.js
@@ -1,11 +1,22 @@
+import { injectIntl } from 'react-intl';
 import { connect } from 'react-redux';
 import { NotificationStack } from 'react-notification';
 import { dismissAlert } from '../../../actions/alerts';
 import { getAlerts } from '../../../selectors';
 
-const mapStateToProps = state => ({
-  notifications: getAlerts(state),
-});
+const mapStateToProps = (state, { intl }) => {
+  const notifications = getAlerts(state);
+
+  notifications.forEach(notification => ['title', 'message'].forEach(key => {
+    const value = notification[key];
+
+    if (typeof value === 'object') {
+      notification[key] = intl.formatMessage(value);
+    }
+  }));
+
+  return { notifications };
+};
 
 const mapDispatchToProps = (dispatch) => {
   return {
@@ -15,4 +26,4 @@ const mapDispatchToProps = (dispatch) => {
   };
 };
 
-export default connect(mapStateToProps, mapDispatchToProps)(NotificationStack);
+export default injectIntl(connect(mapStateToProps, mapDispatchToProps)(NotificationStack));
diff --git a/app/javascript/mastodon/locales/ar.json b/app/javascript/mastodon/locales/ar.json
index 73680a1a1819be68d11570ca06c3ab1e6472c2fd..3d962079327bebb14eb5e49efdcc6cbe952dbf58 100644
--- a/app/javascript/mastodon/locales/ar.json
+++ b/app/javascript/mastodon/locales/ar.json
@@ -28,6 +28,8 @@
   "account.unmute": "إلغاء الكتم عن @{name}",
   "account.unmute_notifications": "إلغاء كتم إخطارات @{name}",
   "account.view_full_profile": "عرض الملف الشخصي كاملا",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "يمكنك ضغط {combo} لتخطّي هذه في المرّة القادمة",
   "bundle_column_error.body": "لقد وقع هناك خطأ أثناء عملية تحميل هذا العنصر.",
   "bundle_column_error.retry": "إعادة المحاولة",
diff --git a/app/javascript/mastodon/locales/bg.json b/app/javascript/mastodon/locales/bg.json
index 1dee16748431562bc6d46d3b582e3606ede1ccfa..39eb05f2a84893cd66eca85c302858ac365c21c2 100644
--- a/app/javascript/mastodon/locales/bg.json
+++ b/app/javascript/mastodon/locales/bg.json
@@ -28,6 +28,8 @@
   "account.unmute": "Unmute @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "You can press {combo} to skip this next time",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/ca.json b/app/javascript/mastodon/locales/ca.json
index 3222daa2fc3509bc484a1c046e43f9f55460de82..33545d86f2d4a33a3307b76a2adb90ca07296955 100644
--- a/app/javascript/mastodon/locales/ca.json
+++ b/app/javascript/mastodon/locales/ca.json
@@ -28,6 +28,8 @@
   "account.unmute": "Treure silenci de @{name}",
   "account.unmute_notifications": "Activar notificacions de @{name}",
   "account.view_full_profile": "Mostra el perfil complet",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Pots premer {combo} per saltar-te això el proper cop",
   "bundle_column_error.body": "S'ha produït un error en carregar aquest component.",
   "bundle_column_error.retry": "Torna-ho a provar",
diff --git a/app/javascript/mastodon/locales/de.json b/app/javascript/mastodon/locales/de.json
index e0fc0ee850bc8c91115daf12ac2cced2d41a1010..7bdb6a3c63d17568e1a93307516d34cdd3b2fbbe 100644
--- a/app/javascript/mastodon/locales/de.json
+++ b/app/javascript/mastodon/locales/de.json
@@ -28,6 +28,8 @@
   "account.unmute": "@{name} nicht mehr stummschalten",
   "account.unmute_notifications": "Benachrichtigungen von @{name} einschalten",
   "account.view_full_profile": "Vollständiges Profil anzeigen",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Du kannst {combo} drücken, um dies beim nächsten Mal zu überspringen",
   "bundle_column_error.body": "Etwas ist beim Laden schiefgelaufen.",
   "bundle_column_error.retry": "Erneut versuchen",
diff --git a/app/javascript/mastodon/locales/defaultMessages.json b/app/javascript/mastodon/locales/defaultMessages.json
index d5b9c09cbf701192ffb09d7230ff8304a93f3559..b983823d4bb2472993b7dd24f2680a9e20b36c58 100644
--- a/app/javascript/mastodon/locales/defaultMessages.json
+++ b/app/javascript/mastodon/locales/defaultMessages.json
@@ -1734,5 +1734,18 @@
       }
     ],
     "path": "app/javascript/mastodon/features/video/index.json"
+  },
+  {
+    "descriptors": [
+      {
+        "defaultMessage": "Oops!",
+        "id": "alert.unexpected.title"
+      },
+      {
+        "defaultMessage": "An unexpected error occurred.",
+        "id": "alert.unexpected.message"
+      }
+    ],
+    "path": "app/javascript/mastodon/middleware/errors.json"
   }
 ]
\ No newline at end of file
diff --git a/app/javascript/mastodon/locales/en.json b/app/javascript/mastodon/locales/en.json
index d0d863f797fef582ec46f34db287fbcf90d5e90f..5553772f4d2780a9b2aa12d3757210ae68f0e123 100644
--- a/app/javascript/mastodon/locales/en.json
+++ b/app/javascript/mastodon/locales/en.json
@@ -28,6 +28,8 @@
   "account.unmute": "Unmute @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "You can press {combo} to skip this next time",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/eo.json b/app/javascript/mastodon/locales/eo.json
index fd687e8b1036ab649e9bd133403b8d99d3ac64ce..35d9edf2ba5577cd0704ced90819bc5802734305 100644
--- a/app/javascript/mastodon/locales/eo.json
+++ b/app/javascript/mastodon/locales/eo.json
@@ -28,6 +28,8 @@
   "account.unmute": "Malsilentigi @{name}",
   "account.unmute_notifications": "Malsilentigi sciigojn de @{name}",
   "account.view_full_profile": "Vidi plenan profilon",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Vi povas premi {combo} por preterpasi sekvafoje",
   "bundle_column_error.body": "Io misfunkciis en la ŝargado de ĉi tiu elemento.",
   "bundle_column_error.retry": "Bonvolu reprovi",
diff --git a/app/javascript/mastodon/locales/es.json b/app/javascript/mastodon/locales/es.json
index 2107a15258dc2f1e7bf7f61b284f8b74dd94d185..e69938b0fa1ba90f057cf3efe9df4e8620898cd8 100644
--- a/app/javascript/mastodon/locales/es.json
+++ b/app/javascript/mastodon/locales/es.json
@@ -28,6 +28,8 @@
   "account.unmute": "Dejar de silenciar a @{name}",
   "account.unmute_notifications": "Dejar de silenciar las notificaciones de @{name}",
   "account.view_full_profile": "Ver perfil completo",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Puedes presionar {combo} para saltear este aviso la próxima vez",
   "bundle_column_error.body": "Algo salió mal al cargar este componente.",
   "bundle_column_error.retry": "Inténtalo de nuevo",
diff --git a/app/javascript/mastodon/locales/fa.json b/app/javascript/mastodon/locales/fa.json
index 455dc5d9f5df0404b3226578c4591a37757d0f01..c9695d0a457c0c767ada9b8c2615e9b08ec8f4e9 100644
--- a/app/javascript/mastodon/locales/fa.json
+++ b/app/javascript/mastodon/locales/fa.json
@@ -28,6 +28,8 @@
   "account.unmute": "باصدا کردن @{name}",
   "account.unmute_notifications": "باصداکردن اعلان‌ها از طرف @{name}",
   "account.view_full_profile": "نمایش نمایهٔ کامل",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "دکمهٔ {combo} را بزنید تا دیگر این را نبینید",
   "bundle_column_error.body": "هنگام بازکردن این بخش خطایی رخ داد.",
   "bundle_column_error.retry": "تلاش دوباره",
diff --git a/app/javascript/mastodon/locales/fi.json b/app/javascript/mastodon/locales/fi.json
index 1741445edbb94e609024ca25c190ed0f6f9c1659..cbdffec106c355f85d543ac409e9d275c3e74f9e 100644
--- a/app/javascript/mastodon/locales/fi.json
+++ b/app/javascript/mastodon/locales/fi.json
@@ -28,6 +28,8 @@
   "account.unmute": "Poista mykistys käyttäjältä @{name}",
   "account.unmute_notifications": "Poista mykistys käyttäjän @{name} ilmoituksilta",
   "account.view_full_profile": "Näytä koko profiili",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Voit painaa näppäimiä {combo} ohittaaksesi tämän ensi kerralla",
   "bundle_column_error.body": "Jokin meni vikaan tätä komponenttia ladatessa.",
   "bundle_column_error.retry": "Yritä uudestaan",
diff --git a/app/javascript/mastodon/locales/fr.json b/app/javascript/mastodon/locales/fr.json
index 40fd6163efecdc3d12651872584b93f8340034d5..8c56a7558382483993f90c319fc46b19107f289e 100644
--- a/app/javascript/mastodon/locales/fr.json
+++ b/app/javascript/mastodon/locales/fr.json
@@ -28,6 +28,8 @@
   "account.unmute": "Ne plus masquer",
   "account.unmute_notifications": "Réactiver les notifications de @{name}",
   "account.view_full_profile": "Afficher le profil complet",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Vous pouvez appuyer sur {combo} pour pouvoir passer ceci, la prochaine fois",
   "bundle_column_error.body": "Une erreur s’est produite lors du chargement de ce composant.",
   "bundle_column_error.retry": "Réessayer",
diff --git a/app/javascript/mastodon/locales/gl.json b/app/javascript/mastodon/locales/gl.json
index edfb9cfcb9832294c18d755f135948a2e3c6117d..c5cedd60a7ff2f7a072d7cb784cce843daf11196 100644
--- a/app/javascript/mastodon/locales/gl.json
+++ b/app/javascript/mastodon/locales/gl.json
@@ -28,6 +28,8 @@
   "account.unmute": "Non acalar @{name}",
   "account.unmute_notifications": "Desbloquear as notificacións de @{name}",
   "account.view_full_profile": "Ver o perfil completo",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Pulse {combo} para saltar esto a próxima vez",
   "bundle_column_error.body": "Houbo un fallo mentras se cargaba este compoñente.",
   "bundle_column_error.retry": "Inténteo de novo",
diff --git a/app/javascript/mastodon/locales/he.json b/app/javascript/mastodon/locales/he.json
index b637ae4147aa4a13100045f6a9442ec2ffc667f6..fe6f9bbb138b00f5535cc954d20f38027d14215c 100644
--- a/app/javascript/mastodon/locales/he.json
+++ b/app/javascript/mastodon/locales/he.json
@@ -28,6 +28,8 @@
   "account.unmute": "הפסקת השתקת @{name}",
   "account.unmute_notifications": "להפסיק הסתרת הודעות מעם @{name}",
   "account.view_full_profile": "הראה אודות מלאות",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "ניתן להקיש {combo} כדי לדלג בפעם הבאה",
   "bundle_column_error.body": "משהו השתבש בעת הצגת הרכיב הזה.",
   "bundle_column_error.retry": "לנסות שוב",
diff --git a/app/javascript/mastodon/locales/hr.json b/app/javascript/mastodon/locales/hr.json
index 4b64d796dc2d11a3c2b0c7273b6f0b2c3ee32ff3..11cd1bff245249342ff571724a1e0d4593624fe9 100644
--- a/app/javascript/mastodon/locales/hr.json
+++ b/app/javascript/mastodon/locales/hr.json
@@ -28,6 +28,8 @@
   "account.unmute": "Poništi utišavanje @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Možeš pritisnuti {combo} kako bi ovo preskočio sljedeći put",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/hu.json b/app/javascript/mastodon/locales/hu.json
index 79888e41e41eb57ab0cb9848064235662058da67..1ea65768a25de05430d386486e84beb6fc2e5103 100644
--- a/app/javascript/mastodon/locales/hu.json
+++ b/app/javascript/mastodon/locales/hu.json
@@ -28,6 +28,8 @@
   "account.unmute": "@{name} kinémítása",
   "account.unmute_notifications": "@{name} értesítéseinek kinémítása",
   "account.view_full_profile": "Teljes profil megtekintése",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Megnyomhatod {combo}, hogy átugord következő alkalommal",
   "bundle_column_error.body": "Hiba történt a komponens betöltése közben.",
   "bundle_column_error.retry": "Próbálja újra",
diff --git a/app/javascript/mastodon/locales/hy.json b/app/javascript/mastodon/locales/hy.json
index 932ff1565f9668abf473561a085f1cecaf962fbe..e9638bf96eb562bd222f4786f58419aa0b55bf56 100644
--- a/app/javascript/mastodon/locales/hy.json
+++ b/app/javascript/mastodon/locales/hy.json
@@ -28,6 +28,8 @@
   "account.unmute": "Ապալռեցնել @{name}֊ին",
   "account.unmute_notifications": "Միացնել ծանուցումները @{name}֊ից",
   "account.view_full_profile": "Ô´Õ«Õ¿Õ¥Õ¬ Õ¡Õ´Õ¢Õ¸Õ²Õ»Õ¡Õ¯Õ¡Õ¶ Õ¿Õ¡Ö€Õ¢Õ¥Ö€Õ¡Õ¯Õ¨Ö‰",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Կարող ես սեղմել {combo}՝ սա հաջորդ անգամ բաց թողնելու համար",
   "bundle_column_error.body": "Այս բաղադրիչը բեռնելու ընթացքում ինչ֊որ բան խափանվեց։",
   "bundle_column_error.retry": "Ô¿Ö€Õ¯Õ«Õ¶ ÖƒÕ¸Ö€Õ±Õ¥Õ¬",
diff --git a/app/javascript/mastodon/locales/id.json b/app/javascript/mastodon/locales/id.json
index bc4294679ec4be62288518c117df503034d23e48..c8d8ebe7680b6add5c8e489232958e1d1129672f 100644
--- a/app/javascript/mastodon/locales/id.json
+++ b/app/javascript/mastodon/locales/id.json
@@ -28,6 +28,8 @@
   "account.unmute": "Berhenti membisukan @{name}",
   "account.unmute_notifications": "Munculkan notifikasi dari @{name}",
   "account.view_full_profile": "Lihat profil lengkap",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Anda dapat menekan {combo} untuk melewati ini",
   "bundle_column_error.body": "Kesalahan terjadi saat memuat komponen ini.",
   "bundle_column_error.retry": "Coba lagi",
diff --git a/app/javascript/mastodon/locales/io.json b/app/javascript/mastodon/locales/io.json
index 5ea982f466f4b3bf8b0ca686d1d2df2f14467a8c..a2e9af8ef1a0000e638a783c03c045ae7d216105 100644
--- a/app/javascript/mastodon/locales/io.json
+++ b/app/javascript/mastodon/locales/io.json
@@ -28,6 +28,8 @@
   "account.unmute": "Ne plus celar @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Tu povas presar sur {combo} por omisar co en la venonta foyo",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/it.json b/app/javascript/mastodon/locales/it.json
index 068598de2ec4c878e0190f7d4ccf1191fdafbd1f..40ea9b26de16b8c89666a29f1612a6b348bd0399 100644
--- a/app/javascript/mastodon/locales/it.json
+++ b/app/javascript/mastodon/locales/it.json
@@ -28,6 +28,8 @@
   "account.unmute": "Non silenziare @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Puoi premere {combo} per saltare questo passaggio la prossima volta",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/ja.json b/app/javascript/mastodon/locales/ja.json
index 0b88ac2df20454df55e8fc585417524c33581318..08f5e79629c71bd008e92990e41d26a950c76a9d 100644
--- a/app/javascript/mastodon/locales/ja.json
+++ b/app/javascript/mastodon/locales/ja.json
@@ -28,6 +28,8 @@
   "account.unmute": "@{name}さんのミュートを解除",
   "account.unmute_notifications": "@{name}さんからの通知を受け取る",
   "account.view_full_profile": "全ての情報を見る",
+  "alert.unexpected.message": "不明なエラーが発生しました",
+  "alert.unexpected.title": "エラー",
   "boost_modal.combo": "次からは{combo}を押せばスキップできます",
   "bundle_column_error.body": "コンポーネントの読み込み中に問題が発生しました。",
   "bundle_column_error.retry": "再試行",
diff --git a/app/javascript/mastodon/locales/ko.json b/app/javascript/mastodon/locales/ko.json
index 532c1f04d0eaa046cd9ab6e2f2dcbc585b31e27a..bde4397f309b6c799b3419a644bbafba09f4bb7f 100644
--- a/app/javascript/mastodon/locales/ko.json
+++ b/app/javascript/mastodon/locales/ko.json
@@ -28,6 +28,8 @@
   "account.unmute": "뮤트 해제",
   "account.unmute_notifications": "@{name}의 알림 뮤트 해제",
   "account.view_full_profile": "전체 프로필 보기",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "다음부터 {combo}를 누르면 이 과정을 건너뛸 수 있습니다.",
   "bundle_column_error.body": "컴포넌트를 불러오는 과정에서 문제가 발생했습니다.",
   "bundle_column_error.retry": "다시 시도",
diff --git a/app/javascript/mastodon/locales/nl.json b/app/javascript/mastodon/locales/nl.json
index a83971f00bf9872fe9e183a0cc39b5dfe5dc0f5f..140be0dca47aad904a65dc420f4a0ffce798c5ec 100644
--- a/app/javascript/mastodon/locales/nl.json
+++ b/app/javascript/mastodon/locales/nl.json
@@ -28,6 +28,8 @@
   "account.unmute": "@{name} niet meer negeren",
   "account.unmute_notifications": "@{name} meldingen niet meer negeren",
   "account.view_full_profile": "Volledig profiel tonen",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Je kunt {combo} klikken om dit de volgende keer over te slaan",
   "bundle_column_error.body": "Tijdens het laden van dit onderdeel is er iets fout gegaan.",
   "bundle_column_error.retry": "Opnieuw proberen",
diff --git a/app/javascript/mastodon/locales/no.json b/app/javascript/mastodon/locales/no.json
index aaad033e29987781f93e8bfaef9c02bd7842c0a6..4d6ac133e364ba191fc3c106e561294c97e619e9 100644
--- a/app/javascript/mastodon/locales/no.json
+++ b/app/javascript/mastodon/locales/no.json
@@ -28,6 +28,8 @@
   "account.unmute": "Avdemp @{name}",
   "account.unmute_notifications": "Vis varsler fra @{name}",
   "account.view_full_profile": "Vis hele profilen",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "You kan trykke {combo} for å hoppe over dette neste gang",
   "bundle_column_error.body": "Noe gikk galt mens denne komponenten lastet.",
   "bundle_column_error.retry": "Prøv igjen",
diff --git a/app/javascript/mastodon/locales/oc.json b/app/javascript/mastodon/locales/oc.json
index f93fe29f6c76a370212b2aad49bc9c796bea2240..24dfa937535215646abe589765827e2b1f4db1a0 100644
--- a/app/javascript/mastodon/locales/oc.json
+++ b/app/javascript/mastodon/locales/oc.json
@@ -28,6 +28,8 @@
   "account.unmute": "Quitar de rescondre @{name}",
   "account.unmute_notifications": "Mostrar las notificacions de @{name}",
   "account.view_full_profile": "Veire lo perfil complèt",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Podètz botar {combo} per passar aquò lo còp que ven",
   "bundle_column_error.body": "Quicòm a fach mèuca pendent lo cargament d’aqueste compausant.",
   "bundle_column_error.retry": "Tornar ensajar",
diff --git a/app/javascript/mastodon/locales/pl.json b/app/javascript/mastodon/locales/pl.json
index 8496495f5d395b264e52479edd01620e57c6fd84..0b6f178f8b6081d49162987c2ece91f3fc42c6f9 100644
--- a/app/javascript/mastodon/locales/pl.json
+++ b/app/javascript/mastodon/locales/pl.json
@@ -28,6 +28,8 @@
   "account.unmute": "Cofnij wyciszenie @{name}",
   "account.unmute_notifications": "Cofnij wyciszenie powiadomień od @{name}",
   "account.view_full_profile": "Wyświetl pełny profil",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Naciśnij {combo}, aby pominąć to następnym razem",
   "bundle_column_error.body": "Coś poszło nie tak podczas ładowania tego składnika.",
   "bundle_column_error.retry": "Spróbuj ponownie",
diff --git a/app/javascript/mastodon/locales/pt-BR.json b/app/javascript/mastodon/locales/pt-BR.json
index c90fb37a04c7b8309bf001b91c9f22c60a76b8b7..dcaeaced9af67aab5918411ea6323551d940591c 100644
--- a/app/javascript/mastodon/locales/pt-BR.json
+++ b/app/javascript/mastodon/locales/pt-BR.json
@@ -28,6 +28,8 @@
   "account.unmute": "Não silenciar @{name}",
   "account.unmute_notifications": "Retirar silêncio das notificações vindas de @{name}",
   "account.view_full_profile": "Ver perfil completo",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Você pode pressionar {combo} para ignorar este diálogo na próxima vez",
   "bundle_column_error.body": "Algo de errado aconteceu enquanto este componente era carregado.",
   "bundle_column_error.retry": "Tente novamente",
diff --git a/app/javascript/mastodon/locales/pt.json b/app/javascript/mastodon/locales/pt.json
index 3b20cf4e6b2213ad1165855ece3a9f6104b51348..4725a82da0460bf116177e5c225212fd30d9f360 100644
--- a/app/javascript/mastodon/locales/pt.json
+++ b/app/javascript/mastodon/locales/pt.json
@@ -28,6 +28,8 @@
   "account.unmute": "Não silenciar @{name}",
   "account.unmute_notifications": "Deixar de silenciar @{name}",
   "account.view_full_profile": "Ver perfil completo",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Pode clicar {combo} para não voltar a ver",
   "bundle_column_error.body": "Algo de errado aconteceu enquanto este componente era carregado.",
   "bundle_column_error.retry": "Tente de novo",
diff --git a/app/javascript/mastodon/locales/ru.json b/app/javascript/mastodon/locales/ru.json
index ec21b5d5598d71e8591db2d4fc67b5d6f3be7980..8e7d36659b199b3e673636ea3c4121ff37c0d8cf 100644
--- a/app/javascript/mastodon/locales/ru.json
+++ b/app/javascript/mastodon/locales/ru.json
@@ -28,6 +28,8 @@
   "account.unmute": "Снять глушение",
   "account.unmute_notifications": "Показывать уведомления от @{name}",
   "account.view_full_profile": "Показать полный профиль",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Нажмите {combo}, чтобы пропустить это в следующий раз",
   "bundle_column_error.body": "Что-то пошло не так при загрузке этого компонента.",
   "bundle_column_error.retry": "Попробовать снова",
diff --git a/app/javascript/mastodon/locales/sk.json b/app/javascript/mastodon/locales/sk.json
index 683f2aadbd18648155f65ad6a38be32dec0ddbe8..e3b323943c8ecb7f46fb1e44ded7ec599d3c5d53 100644
--- a/app/javascript/mastodon/locales/sk.json
+++ b/app/javascript/mastodon/locales/sk.json
@@ -28,6 +28,8 @@
   "account.unmute": "Prestať ignorovať @{name}",
   "account.unmute_notifications": "Odtĺmiť notifikácie od @{name}",
   "account.view_full_profile": "Pozri celý profil",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Nabudúce môžete kliknúť {combo} aby ste preskočili",
   "bundle_column_error.body": "Nastala chyba pri načítaní tohto komponentu.",
   "bundle_column_error.retry": "Skúste znova",
diff --git a/app/javascript/mastodon/locales/sr-Latn.json b/app/javascript/mastodon/locales/sr-Latn.json
index c6512cda45912c5e76822d675449ef02e4b21036..d38e8e3af78b6628d973e9a718eb234754f070b3 100644
--- a/app/javascript/mastodon/locales/sr-Latn.json
+++ b/app/javascript/mastodon/locales/sr-Latn.json
@@ -28,6 +28,8 @@
   "account.unmute": "Ukloni ućutkavanje korisniku @{name}",
   "account.unmute_notifications": "Uključi nazad obaveštenja od korisnika @{name}",
   "account.view_full_profile": "Vidi ceo profil",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Možete pritisnuti {combo} da preskočite ovo sledeći put",
   "bundle_column_error.body": "Nešto je pošlo po zlu prilikom učitavanja ove komponente.",
   "bundle_column_error.retry": "Pokušajte ponovo",
diff --git a/app/javascript/mastodon/locales/sr.json b/app/javascript/mastodon/locales/sr.json
index 93fbe5960f1351ab48d8dcf63f3412265bd8dc21..3be0c89ee1583bd0e9674880da32d6cc222a68bd 100644
--- a/app/javascript/mastodon/locales/sr.json
+++ b/app/javascript/mastodon/locales/sr.json
@@ -28,6 +28,8 @@
   "account.unmute": "Уклони ућуткавање кориснику @{name}",
   "account.unmute_notifications": "Укључи назад обавештења од корисника @{name}",
   "account.view_full_profile": "Види цео профил",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Можете притиснути {combo} да прескочите ово следећи пут",
   "bundle_column_error.body": "Нешто је пошло по злу приликом учитавања ове компоненте.",
   "bundle_column_error.retry": "Покушајте поново",
diff --git a/app/javascript/mastodon/locales/sv.json b/app/javascript/mastodon/locales/sv.json
index 4fa129173e1135ddd297bb8fed67b9ae7cc11b09..a13ba9847e727016a8687e2e0c01d8ad94b247ea 100644
--- a/app/javascript/mastodon/locales/sv.json
+++ b/app/javascript/mastodon/locales/sv.json
@@ -28,6 +28,8 @@
   "account.unmute": "Ta bort tystad @{name}",
   "account.unmute_notifications": "Återaktivera notifikationer från @{name}",
   "account.view_full_profile": "Visa hela profilen",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Du kan trycka {combo} för att slippa denna nästa gång",
   "bundle_column_error.body": "Något gick fel när du laddade denna komponent.",
   "bundle_column_error.retry": "Försök igen",
diff --git a/app/javascript/mastodon/locales/th.json b/app/javascript/mastodon/locales/th.json
index 95a933b4061d51afb681bd835298873a1e27430b..59ff10b468a4dd44e39ed75f2568622de7bf3769 100644
--- a/app/javascript/mastodon/locales/th.json
+++ b/app/javascript/mastodon/locales/th.json
@@ -28,6 +28,8 @@
   "account.unmute": "Unmute @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "You can press {combo} to skip this next time",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/tr.json b/app/javascript/mastodon/locales/tr.json
index baaa5c97af03074879bf59bcad13ea82edcb9dc3..e83af319ec2abb33b08f0054f70ffd3385f34114 100644
--- a/app/javascript/mastodon/locales/tr.json
+++ b/app/javascript/mastodon/locales/tr.json
@@ -28,6 +28,8 @@
   "account.unmute": "Sesi aç @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Bir dahaki sefere {combo} tuÅŸuna basabilirsiniz",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/uk.json b/app/javascript/mastodon/locales/uk.json
index 1755c55b4d515693bb17f9ef8fa13628fdb39034..accc2d0277440edd8f28d3246ff8d0b74f75d69e 100644
--- a/app/javascript/mastodon/locales/uk.json
+++ b/app/javascript/mastodon/locales/uk.json
@@ -28,6 +28,8 @@
   "account.unmute": "Зняти глушення",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "View full profile",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "Ви можете натиснути {combo}, щоб пропустити це наступного разу",
   "bundle_column_error.body": "Something went wrong while loading this component.",
   "bundle_column_error.retry": "Try again",
diff --git a/app/javascript/mastodon/locales/zh-CN.json b/app/javascript/mastodon/locales/zh-CN.json
index d031c85f3112f8017eb08a828148c6be50e14821..b9a912fb034169d7bfa19e636a38ccba2fa7b4fe 100644
--- a/app/javascript/mastodon/locales/zh-CN.json
+++ b/app/javascript/mastodon/locales/zh-CN.json
@@ -28,6 +28,8 @@
   "account.unmute": "不再隐藏 @{name}",
   "account.unmute_notifications": "不再隐藏来自 @{name} 的通知",
   "account.view_full_profile": "查看完整资料",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "下次按住 {combo} 即可跳过此提示",
   "bundle_column_error.body": "载入这个组件时发生了错误。",
   "bundle_column_error.retry": "重试",
diff --git a/app/javascript/mastodon/locales/zh-HK.json b/app/javascript/mastodon/locales/zh-HK.json
index d3ad238ad2883e5a01c462f5c8dc45d43557f12a..91b1d00afb69df692dd2e01bc357c3f7263cc4d2 100644
--- a/app/javascript/mastodon/locales/zh-HK.json
+++ b/app/javascript/mastodon/locales/zh-HK.json
@@ -28,6 +28,8 @@
   "account.unmute": "取消 @{name} 的靜音",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "查看完整資料",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "如你想在下次路過這顯示，請按{combo}，",
   "bundle_column_error.body": "加載本組件出錯。",
   "bundle_column_error.retry": "重試",
diff --git a/app/javascript/mastodon/locales/zh-TW.json b/app/javascript/mastodon/locales/zh-TW.json
index 3a5eade411b07c751a583c48a6af292999115f47..7e845c65082fc5ca08de470c8adb255c3317b899 100644
--- a/app/javascript/mastodon/locales/zh-TW.json
+++ b/app/javascript/mastodon/locales/zh-TW.json
@@ -28,6 +28,8 @@
   "account.unmute": "不再消音 @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account.view_full_profile": "查看完整資訊",
+  "alert.unexpected.message": "An unexpected error occurred.",
+  "alert.unexpected.title": "Oops!",
   "boost_modal.combo": "下次你可以按 {combo} 來跳過",
   "bundle_column_error.body": "加載本組件出錯。",
   "bundle_column_error.retry": "重試",
diff --git a/app/javascript/mastodon/middleware/errors.js b/app/javascript/mastodon/middleware/errors.js
index b2c5f0898b459eb525cf9c3a1e861216f941643b..72e5631e6dae343154d59fd06d10501dace2d9c9 100644
--- a/app/javascript/mastodon/middleware/errors.js
+++ b/app/javascript/mastodon/middleware/errors.js
@@ -1,7 +1,13 @@
+import { defineMessages } from 'react-intl';
 import { showAlert } from '../actions/alerts';
 
 const defaultFailSuffix = 'FAIL';
 
+const messages = defineMessages({
+  unexpectedTitle: { id: 'alert.unexpected.title', defaultMessage: 'Oops!' },
+  unexpectedMessage: { id: 'alert.unexpected.message', defaultMessage: 'An unexpected error occurred.' },
+});
+
 export default function errorsMiddleware() {
   return ({ dispatch }) => next => action => {
     if (action.type && !action.skipAlert) {
@@ -21,7 +27,7 @@ export default function errorsMiddleware() {
           dispatch(showAlert(title, message));
         } else {
           console.error(action.error);
-          dispatch(showAlert('Oops!', 'An unexpected error occurred.'));
+          dispatch(showAlert(messages.unexpectedTitle, messages.unexpectedMessage));
         }
       }
     }