fix(post form): block temporary media links

public/translations/ar/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "مستضافة خارج 5chan",
   "media_failed_to_load_open_source": "افتح الملف الأصلي",
   "media_failed_to_load_inline": "فشلت الصورة الخارجية من {{host}}. جرّب VPN.",
-  "media_failed_to_load_inline_unknown": "فشلت الصورة الخارجية. جرّب VPN."
+  "media_failed_to_load_inline_unknown": "فشلت الصورة الخارجية. جرّب VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/bn/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "5chan-এর বাইরে হোস্ট করা",
   "media_failed_to_load_open_source": "মূল ফাইল খুলুন",
   "media_failed_to_load_inline": "{{host}} থেকে বাইরের ছবি লোড হয়নি। VPN চেষ্টা করুন।",
-  "media_failed_to_load_inline_unknown": "বাইরের ছবি লোড হয়নি। VPN চেষ্টা করুন।"
+  "media_failed_to_load_inline_unknown": "বাইরের ছবি লোড হয়নি। VPN চেষ্টা করুন।",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/cs/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Hostováno mimo 5chan",
   "media_failed_to_load_open_source": "Otevřít původní soubor",
   "media_failed_to_load_inline": "Externí obrázek z {{host}} selhal. Zkuste VPN.",
-  "media_failed_to_load_inline_unknown": "Externí obrázek selhal. Zkuste VPN."
+  "media_failed_to_load_inline_unknown": "Externí obrázek selhal. Zkuste VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/da/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Hostet uden for 5chan",
   "media_failed_to_load_open_source": "Åbn originalfil",
   "media_failed_to_load_inline": "Eksternt billede fra {{host}} fejlede. Prøv VPN.",
-  "media_failed_to_load_inline_unknown": "Eksternt billede fejlede. Prøv VPN."
+  "media_failed_to_load_inline_unknown": "Eksternt billede fejlede. Prøv VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/de/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Nicht auf 5chan gehostet",
   "media_failed_to_load_open_source": "Originaldatei öffnen",
   "media_failed_to_load_inline": "Externes Bild von {{host}} fehlgeschlagen. VPN versuchen.",
-  "media_failed_to_load_inline_unknown": "Externes Bild fehlgeschlagen. VPN versuchen."
+  "media_failed_to_load_inline_unknown": "Externes Bild fehlgeschlagen. VPN versuchen.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/el/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Φιλοξενείται εκτός 5chan",
   "media_failed_to_load_open_source": "Άνοιγμα αρχικού αρχείου",
   "media_failed_to_load_inline": "Η εξωτερική εικόνα από {{host}} απέτυχε. Δοκιμάστε VPN.",
-  "media_failed_to_load_inline_unknown": "Η εξωτερική εικόνα απέτυχε. Δοκιμάστε VPN."
+  "media_failed_to_load_inline_unknown": "Η εξωτερική εικόνα απέτυχε. Δοκιμάστε VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/en/default.json

@@ -187,6 +187,7 @@
   "filtered_threads": "Filtered threads",
   "no_board_selected_warning": "Please select a board before posting.",
   "invalid_url_alert": "The provided link is not a valid URL.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead.",
   "empty_comment_alert": "Cannot post empty comment.",
   "stored_locally": "Stored locally (in {{location}} data), not synced across devices.",
   "choose_one": "Choose one:",

public/translations/es/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Host externo, no 5chan",
   "media_failed_to_load_open_source": "Abrir archivo original",
   "media_failed_to_load_inline": "Falló la imagen externa de {{host}}. Prueba una VPN.",
-  "media_failed_to_load_inline_unknown": "Falló la imagen externa. Prueba una VPN."
+  "media_failed_to_load_inline_unknown": "Falló la imagen externa. Prueba una VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/fa/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "میزبان خارجی، نه 5chan",
   "media_failed_to_load_open_source": "باز کردن فایل اصلی",
   "media_failed_to_load_inline": "تصویر خارجی از {{host}} بارگیری نشد. VPN را امتحان کنید.",
-  "media_failed_to_load_inline_unknown": "تصویر خارجی بارگیری نشد. VPN را امتحان کنید."
+  "media_failed_to_load_inline_unknown": "تصویر خارجی بارگیری نشد. VPN را امتحان کنید.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/fi/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Ulkoinen host, ei 5chan",
   "media_failed_to_load_open_source": "Avaa alkuperäinen tiedosto",
   "media_failed_to_load_inline": "Ulkoinen kuva sivustolta {{host}} epäonnistui. Kokeile VPN:ää.",
-  "media_failed_to_load_inline_unknown": "Ulkoinen kuva epäonnistui. Kokeile VPN:ää."
+  "media_failed_to_load_inline_unknown": "Ulkoinen kuva epäonnistui. Kokeile VPN:ää.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/fil/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Panlabas na host, hindi 5chan",
   "media_failed_to_load_open_source": "Buksan ang orihinal na file",
   "media_failed_to_load_inline": "Nabigo ang panlabas na larawan mula sa {{host}}. Subukan ang VPN.",
-  "media_failed_to_load_inline_unknown": "Nabigo ang panlabas na larawan. Subukan ang VPN."
+  "media_failed_to_load_inline_unknown": "Nabigo ang panlabas na larawan. Subukan ang VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/fr/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Hôte externe, pas 5chan",
   "media_failed_to_load_open_source": "Ouvrir le fichier original",
   "media_failed_to_load_inline": "L'image externe de {{host}} a échoué. Essayez un VPN.",
-  "media_failed_to_load_inline_unknown": "L'image externe a échoué. Essayez un VPN."
+  "media_failed_to_load_inline_unknown": "L'image externe a échoué. Essayez un VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/he/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "מארח חיצוני, לא 5chan",
   "media_failed_to_load_open_source": "פתח את הקובץ המקורי",
   "media_failed_to_load_inline": "התמונה החיצונית מ-{{host}} נכשלה. נסה VPN.",
-  "media_failed_to_load_inline_unknown": "התמונה החיצונית נכשלה. נסה VPN."
+  "media_failed_to_load_inline_unknown": "התמונה החיצונית נכשלה. נסה VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/hi/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "बाहरी होस्ट, 5chan नहीं",
   "media_failed_to_load_open_source": "मूल फ़ाइल खोलें",
   "media_failed_to_load_inline": "{{host}} से बाहरी छवि लोड नहीं हुई। VPN आज़माएँ।",
-  "media_failed_to_load_inline_unknown": "बाहरी छवि लोड नहीं हुई। VPN आज़माएँ।"
+  "media_failed_to_load_inline_unknown": "बाहरी छवि लोड नहीं हुई। VPN आज़माएँ।",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/hu/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Külső host, nem 5chan",
   "media_failed_to_load_open_source": "Eredeti fájl megnyitása",
   "media_failed_to_load_inline": "A külső kép innen nem töltődött be: {{host}}. Próbálj VPN-t.",
-  "media_failed_to_load_inline_unknown": "A külső kép nem töltődött be. Próbálj VPN-t."
+  "media_failed_to_load_inline_unknown": "A külső kép nem töltődött be. Próbálj VPN-t.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/id/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Host eksternal, bukan 5chan",
   "media_failed_to_load_open_source": "Buka file asli",
   "media_failed_to_load_inline": "Gambar eksternal dari {{host}} gagal. Coba VPN.",
-  "media_failed_to_load_inline_unknown": "Gambar eksternal gagal. Coba VPN."
+  "media_failed_to_load_inline_unknown": "Gambar eksternal gagal. Coba VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/it/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Host esterno, non 5chan",
   "media_failed_to_load_open_source": "Apri file originale",
   "media_failed_to_load_inline": "Immagine esterna da {{host}} non caricata. Prova una VPN.",
-  "media_failed_to_load_inline_unknown": "Immagine esterna non caricata. Prova una VPN."
+  "media_failed_to_load_inline_unknown": "Immagine esterna non caricata. Prova una VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/ja/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "外部ホスト、5chan ではありません",
   "media_failed_to_load_open_source": "元のファイルを開く",
   "media_failed_to_load_inline": "{{host}} の外部画像を読み込めませんでした。VPN を試してください。",
-  "media_failed_to_load_inline_unknown": "外部画像を読み込めませんでした。VPN を試してください。"
+  "media_failed_to_load_inline_unknown": "外部画像を読み込めませんでした。VPN を試してください。",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/ko/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "외부 호스트, 5chan 아님",
   "media_failed_to_load_open_source": "원본 파일 열기",
   "media_failed_to_load_inline": "{{host}}의 외부 이미지를 불러오지 못했습니다. VPN을 시도하세요.",
-  "media_failed_to_load_inline_unknown": "외부 이미지를 불러오지 못했습니다. VPN을 시도하세요."
+  "media_failed_to_load_inline_unknown": "외부 이미지를 불러오지 못했습니다. VPN을 시도하세요.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/mr/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "बाह्य होस्ट, 5chan नाही",
   "media_failed_to_load_open_source": "मूळ फाइल उघडा",
   "media_failed_to_load_inline": "{{host}} वरील बाह्य प्रतिमा लोड झाली नाही. VPN वापरून पाहा.",
-  "media_failed_to_load_inline_unknown": "बाह्य प्रतिमा लोड झाली नाही. VPN वापरून पाहा."
+  "media_failed_to_load_inline_unknown": "बाह्य प्रतिमा लोड झाली नाही. VPN वापरून पाहा.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/nl/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Externe host, niet 5chan",
   "media_failed_to_load_open_source": "Origineel bestand openen",
   "media_failed_to_load_inline": "Externe afbeelding van {{host}} mislukt. Probeer VPN.",
-  "media_failed_to_load_inline_unknown": "Externe afbeelding mislukt. Probeer VPN."
+  "media_failed_to_load_inline_unknown": "Externe afbeelding mislukt. Probeer VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/no/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Ekstern host, ikke 5chan",
   "media_failed_to_load_open_source": "Åpne originalfil",
   "media_failed_to_load_inline": "Eksternt bilde fra {{host}} kunne ikke lastes. Prøv VPN.",
-  "media_failed_to_load_inline_unknown": "Eksternt bilde kunne ikke lastes. Prøv VPN."
+  "media_failed_to_load_inline_unknown": "Eksternt bilde kunne ikke lastes. Prøv VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/pl/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Zewnętrzny host, nie 5chan",
   "media_failed_to_load_open_source": "Otwórz oryginalny plik",
   "media_failed_to_load_inline": "Obraz zewnętrzny z {{host}} nie załadował się. Spróbuj VPN.",
-  "media_failed_to_load_inline_unknown": "Obraz zewnętrzny nie załadował się. Spróbuj VPN."
+  "media_failed_to_load_inline_unknown": "Obraz zewnętrzny nie załadował się. Spróbuj VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/pt/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Host externo, não 5chan",
   "media_failed_to_load_open_source": "Abrir arquivo original",
   "media_failed_to_load_inline": "Falha na imagem externa de {{host}}. Tente uma VPN.",
-  "media_failed_to_load_inline_unknown": "Falha na imagem externa. Tente uma VPN."
+  "media_failed_to_load_inline_unknown": "Falha na imagem externa. Tente uma VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/ro/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Host extern, nu 5chan",
   "media_failed_to_load_open_source": "Deschide fișierul original",
   "media_failed_to_load_inline": "Imaginea externă de la {{host}} a eșuat. Încearcă VPN.",
-  "media_failed_to_load_inline_unknown": "Imaginea externă a eșuat. Încearcă VPN."
+  "media_failed_to_load_inline_unknown": "Imaginea externă a eșuat. Încearcă VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/ru/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Внешний хост, не 5chan",
   "media_failed_to_load_open_source": "Открыть исходный файл",
   "media_failed_to_load_inline": "Внешнее изображение с {{host}} не загрузилось. Попробуйте VPN.",
-  "media_failed_to_load_inline_unknown": "Внешнее изображение не загрузилось. Попробуйте VPN."
+  "media_failed_to_load_inline_unknown": "Внешнее изображение не загрузилось. Попробуйте VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/sq/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Host i jashtëm, jo 5chan",
   "media_failed_to_load_open_source": "Hap skedarin origjinal",
   "media_failed_to_load_inline": "Imazhi i jashtëm nga {{host}} dështoi. Provoni VPN.",
-  "media_failed_to_load_inline_unknown": "Imazhi i jashtëm dështoi. Provoni VPN."
+  "media_failed_to_load_inline_unknown": "Imazhi i jashtëm dështoi. Provoni VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/sv/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Extern host, inte 5chan",
   "media_failed_to_load_open_source": "Öppna originalfil",
   "media_failed_to_load_inline": "Extern bild från {{host}} kunde inte läsas in. Prova VPN.",
-  "media_failed_to_load_inline_unknown": "Extern bild kunde inte läsas in. Prova VPN."
+  "media_failed_to_load_inline_unknown": "Extern bild kunde inte läsas in. Prova VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/te/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "బాహ్య హోస్ట్, 5chan కాదు",
   "media_failed_to_load_open_source": "అసలు ఫైల్‌ను తెరవండి",
   "media_failed_to_load_inline": "{{host}} నుండి బాహ్య చిత్రం లోడ్ కాలేదు. VPN ప్రయత్నించండి.",
-  "media_failed_to_load_inline_unknown": "బాహ్య చిత్రం లోడ్ కాలేదు. VPN ప్రయత్నించండి."
+  "media_failed_to_load_inline_unknown": "బాహ్య చిత్రం లోడ్ కాలేదు. VPN ప్రయత్నించండి.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/th/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "โฮสต์ภายนอก ไม่ใช่ 5chan",
   "media_failed_to_load_open_source": "เปิดไฟล์ต้นฉบับ",
   "media_failed_to_load_inline": "โหลดรูปภาพภายนอกจาก {{host}} ไม่สำเร็จ ลอง VPN",
-  "media_failed_to_load_inline_unknown": "โหลดรูปภาพภายนอกไม่สำเร็จ ลอง VPN"
+  "media_failed_to_load_inline_unknown": "โหลดรูปภาพภายนอกไม่สำเร็จ ลอง VPN",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/tr/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Harici host, 5chan değil",
   "media_failed_to_load_open_source": "Orijinal dosyayı aç",
   "media_failed_to_load_inline": "{{host}} harici görseli yüklenemedi. VPN deneyin.",
-  "media_failed_to_load_inline_unknown": "Harici görsel yüklenemedi. VPN deneyin."
+  "media_failed_to_load_inline_unknown": "Harici görsel yüklenemedi. VPN deneyin.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/uk/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Зовнішній хост, не 5chan",
   "media_failed_to_load_open_source": "Відкрити оригінальний файл",
   "media_failed_to_load_inline": "Зовнішнє зображення з {{host}} не завантажилося. Спробуйте VPN.",
-  "media_failed_to_load_inline_unknown": "Зовнішнє зображення не завантажилося. Спробуйте VPN."
+  "media_failed_to_load_inline_unknown": "Зовнішнє зображення не завантажилося. Спробуйте VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/ur/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "بیرونی ہوسٹ، 5chan نہیں",
   "media_failed_to_load_open_source": "اصل فائل کھولیں",
   "media_failed_to_load_inline": "{{host}} سے بیرونی تصویر لوڈ نہیں ہوئی۔ VPN آزمائیں۔",
-  "media_failed_to_load_inline_unknown": "بیرونی تصویر لوڈ نہیں ہوئی۔ VPN آزمائیں۔"
+  "media_failed_to_load_inline_unknown": "بیرونی تصویر لوڈ نہیں ہوئی۔ VPN آزمائیں۔",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/vi/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "Máy chủ ngoài, không phải 5chan",
   "media_failed_to_load_open_source": "Mở tệp gốc",
   "media_failed_to_load_inline": "Không tải được ảnh bên ngoài từ {{host}}. Thử VPN.",
-  "media_failed_to_load_inline_unknown": "Không tải được ảnh bên ngoài. Thử VPN."
+  "media_failed_to_load_inline_unknown": "Không tải được ảnh bên ngoài. Thử VPN.",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

public/translations/zh/default.json

@@ -387,5 +387,6 @@
   "media_failed_to_load_source_unknown": "外部主机，不是 5chan",
   "media_failed_to_load_open_source": "打开原始文件",
   "media_failed_to_load_inline": "来自 {{host}} 的外部图片加载失败。试试 VPN。",
-  "media_failed_to_load_inline_unknown": "外部图片加载失败。试试 VPN。"
+  "media_failed_to_load_inline_unknown": "外部图片加载失败。试试 VPN。",
+  "expiring_media_link_alert": "Media from {{domain}} expires quickly. Use a stable media link instead."
 }

src/components/post-form/__tests__/post-form.test.tsx

@@ -52,7 +52,7 @@ const testState = vi.hoisted(() => ({
 
 vi.mock('react-i18next', () => ({
   useTranslation: () => ({
-    t: (key: string) => key,
+    t: (key: string, options?: Record<string, unknown>) => (options?.domain ? `${key}:${options.domain}` : key),
   }),
 }));
 
@@ -401,8 +401,14 @@ describe('PostForm', () => {
     expect(globalThis.alert).toHaveBeenCalledWith('invalid_url_alert');
 
     (globalThis.alert as ReturnType<typeof vi.fn>).mockClear();
-    await dispatchInput(linkInput as HTMLInputElement, '');
     await dispatchInput(textarea as HTMLTextAreaElement, 'A valid body');
+    await dispatchInput(linkInput as HTMLInputElement, 'https://i.4cdn.org/gif/file.jpg');
+    await clickByText(table as HTMLTableElement, 'post');
+    expect(globalThis.alert).not.toHaveBeenCalled();
+    expect(container.textContent).toContain('error: expiring_media_link_alert:i.4cdn.org');
+    expect(testState.publishPostMock).not.toHaveBeenCalled();
+
+    await dispatchInput(linkInput as HTMLInputElement, '');
     await clickByText(table as HTMLTableElement, 'post');
     expect(globalThis.alert).toHaveBeenCalledWith('no_board_selected_warning');
 

src/components/post-form/post-form.module.css

@@ -188,6 +188,11 @@
   color: red;
 }
 
+.formError {
+  margin: 8px 0;
+  padding: 6px 5px;
+}
+
 .status {
   padding: 5px;
 }

src/components/post-form/post-form.tsx

@@ -6,6 +6,7 @@ import { Comment, setAccount, useAccount, useEditedComment } from '@bitsocial/bi
 import getShortAddress from '../../lib/get-short-address';
 import useCommunitiesPagesStore from '@bitsocial/bitsocial-react-hooks/dist/stores/communities-pages';
 import { getDisplayMediaInfoType, getLinkMediaInfo } from '../../lib/utils/media-utils';
+import { getExpiringMediaLinkAlert } from '../../lib/utils/media-link-validation-utils';
 import { getPublishURLFilename, isValidPublishURL, isValidURL } from '../../lib/utils/url-utils';
 import { isAllView, isCatalogView, isModQueueView, isModView, isPostPageView, isSubscriptionsView } from '../../lib/utils/view-utils';
 import { useAccountCommunityAddresses } from '../../hooks/use-account-community-addresses';
@@ -346,6 +347,7 @@ const PostFormTable = ({ closeForm, postCid }: { closeForm: () => void; postCid:
   const accountCommunityAddresses = useAccountCommunityAddresses();
 
   const [lengthError, setLengthError] = useState<string | null>(null);
+  const [formError, setFormError] = useState<string | null>(null);
 
   const checkContentLength = useRef(
     debounce((content: string, t: TFunction) => {
@@ -377,6 +379,7 @@ const PostFormTable = ({ closeForm, postCid }: { closeForm: () => void; postCid:
 
     checkContentLength.cancel();
     setLengthError(null);
+    setFormError(null);
 
     if (!currentTitle && !currentContent && !currentUrl) {
       alert(t('empty_comment_alert'));
@@ -386,6 +389,11 @@ const PostFormTable = ({ closeForm, postCid }: { closeForm: () => void; postCid:
       alert(t('invalid_url_alert'));
       return;
     }
+    const expiringMediaLinkAlert = currentUrl ? getExpiringMediaLinkAlert(currentUrl, t) : null;
+    if (expiringMediaLinkAlert) {
+      setFormError(expiringMediaLinkAlert);
+      return;
+    }
 
     if (currentContent.length > 2000) {
       alert(t('error') + ': ' + t('field_too_long'));
@@ -432,6 +440,7 @@ const PostFormTable = ({ closeForm, postCid }: { closeForm: () => void; postCid:
 
     checkContentLength.cancel();
     setLengthError(null);
+    setFormError(null);
 
     if (!currentContent && !currentUrl) {
       alert(t('empty_comment_alert'));
@@ -442,6 +451,11 @@ const PostFormTable = ({ closeForm, postCid }: { closeForm: () => void; postCid:
       alert(t('invalid_url_alert'));
       return;
     }
+    const expiringMediaLinkAlert = currentUrl ? getExpiringMediaLinkAlert(currentUrl, t) : null;
+    if (expiringMediaLinkAlert) {
+      setFormError(expiringMediaLinkAlert);
+      return;
+    }
 
     if (currentContent.length > 2000) {
       alert(t('error') + ': ' + t('field_too_long'));
@@ -527,8 +541,9 @@ const PostFormTable = ({ closeForm, postCid }: { closeForm: () => void; postCid:
           />
         </tbody>
       </table>
-      {publishPostError && <div className={styles.error}>{publishPostError}</div>}
+      {formError && <div className={`${styles.error} ${styles.formError}`}>{formError}</div>}
-      {publishReplyError && <div className={styles.error}>{publishReplyError}</div>}
+      {publishPostError && <div className={`${styles.error} ${styles.formError}`}>{publishPostError}</div>}
+      {publishReplyError && <div className={`${styles.error} ${styles.formError}`}>{publishReplyError}</div>}
       {publishReplyStateMessage && <div className={styles.status}>{publishReplyStateMessage}</div>}
     </>
   );

src/components/reply-modal/__tests__/reply-modal.test.tsx

@@ -414,6 +414,12 @@ describe('ReplyModal', () => {
     expect(container.textContent).toContain('error: invalid_url_alert');
     expect(testState.setPublishReplyOptionsMock).toHaveBeenCalledWith({ spoiler: true });
 
+    await dispatchInput(linkInput, 'https://temp.sh/example.png');
+    await clickButtonByText('post');
+
+    expect(container.textContent).toContain('error: expiring_media_link_alert:{"domain":"temp.sh"}');
+    expect(testState.publishReplyMock).not.toHaveBeenCalled();
+
     await dispatchInput(linkInput, 'https://example.com/file.png');
     await clickButtonByText('post');
 

src/components/reply-modal/reply-modal.tsx

@@ -3,6 +3,7 @@ import { useLocation, useParams } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
 import type { TFunction } from 'i18next';
 import { setAccount, useAccount } from '@bitsocial/bitsocial-react-hooks';
+import { getExpiringMediaLinkAlert } from '../../lib/utils/media-link-validation-utils';
 import { getPublishURLFilename, isValidPublishURL } from '../../lib/utils/url-utils';
 import { isAllView, isModView, isSubscriptionsView } from '../../lib/utils/view-utils';
 import useSelectedTextStore from '../../stores/use-selected-text-store';
@@ -103,6 +104,11 @@ const ReplyModal = ({ closeModal, showReplyModal, parentCid, parentNumber, threa
       setError(t('error') + ': ' + t('invalid_url_alert'));
       return;
     }
+    const expiringMediaLinkAlert = currentUrl ? getExpiringMediaLinkAlert(currentUrl, t) : null;
+    if (expiringMediaLinkAlert) {
+      setError(expiringMediaLinkAlert);
+      return;
+    }
 
     checkContentLengthRef.current.cancel();
     setLengthError(null);

src/lib/utils/__tests__/url-utils.test.ts

@@ -10,6 +10,7 @@ vi.mock('../clipboard-utils', () => ({
 
 import {
   copyShareLinkToClipboard,
+  getExpiringMediaLinkHostname,
   getHostname,
   getPublishURLFilename,
   is5chanLink,
@@ -62,6 +63,15 @@ describe('url-utils', () => {
     expect(getPublishURLFilename('not-a-url')).toBeNull();
   });
 
+  it('detects publish media hosts with temporary links', () => {
+    expect(getExpiringMediaLinkHostname('https://i.4cdn.org/gif/1712345678900.jpg')).toBe('i.4cdn.org');
+    expect(getExpiringMediaLinkHostname('http://litterbox.catbox.moe/u/example.png')).toBe('litterbox.catbox.moe');
+    expect(getExpiringMediaLinkHostname('https://www.tmpfiles.org/dl/123/file.mp4')).toBe('tmpfiles.org');
+    expect(getExpiringMediaLinkHostname('https://cdn.file.kiwi/example')).toBe('file.kiwi');
+    expect(getExpiringMediaLinkHostname('https://example.com/file.png')).toBeNull();
+    expect(getExpiringMediaLinkHostname('not-a-url')).toBeNull();
+  });
+
   it('copies share links for threads and catalog pages using the production fallback base url', async () => {
     await copyShareLinkToClipboard('music.eth', 'thread', 'cid-123');
     expect(testState.copyToClipboardMock).toHaveBeenCalledWith('https://5chan.app/#/music.eth/thread/cid-123');

src/lib/utils/media-link-validation-utils.ts

@@ -0,0 +1,8 @@
+import { getExpiringMediaLinkHostname } from './url-utils';
+
+type TranslateFn = (key: string, options?: Record<string, unknown>) => string;
+
+export const getExpiringMediaLinkAlert = (url: string, t: TranslateFn): string | null => {
+  const expiringMediaLinkHostname = getExpiringMediaLinkHostname(url);
+  return expiringMediaLinkHostname ? `${t('error')}: ${t('expiring_media_link_alert', { domain: expiringMediaLinkHostname })}` : null;
+};

src/lib/utils/url-utils.ts

@@ -67,6 +67,41 @@ export const normalizePublishURL = (url: string) => {
   return trimmedUrl;
 };
 
+const EXPIRING_MEDIA_LINK_HOSTNAMES = [
+  // 4chan CDN media disappears when threads are pruned, usually after a few hours or days.
+  'i.4cdn.org',
+  // Litterbox temporary uploads can expire after 1 hour, 12 hours, 1 day, or 3 days.
+  'litterbox.catbox.moe',
+  // tmpfiles.org uploads expire after 60 minutes, 6 hours, 12 hours, or 24 hours.
+  'tmpfiles.org',
+  // Filebin uploads are deleted automatically after about 6 days.
+  'filebin.net',
+  // temp.sh files expire after 3 days.
+  'temp.sh',
+  // Termbin pastes are automatically deleted after 1 week.
+  'termbin.com',
+  // Uguu files expire after 3 hours.
+  'uguu.se',
+  // file.kiwi encrypted files are deleted after about 4 days by default.
+  'file.kiwi',
+] as const;
+
+const normalizeHostnameForMatching = (hostname: string) => hostname.toLowerCase().replace(/^www\./, '');
+
+export const getExpiringMediaLinkHostname = (url: string): string | null => {
+  try {
+    const parsedUrl = new URL(normalizePublishURL(url));
+    if (parsedUrl.protocol !== 'https:') {
+      return null;
+    }
+
+    const hostname = normalizeHostnameForMatching(parsedUrl.hostname);
+    return EXPIRING_MEDIA_LINK_HOSTNAMES.find((expiringHostname) => hostname === expiringHostname || hostname.endsWith(`.${expiringHostname}`)) || null;
+  } catch {
+    return null;
+  }
+};
+
 export const isValidPublishURL = (url: string) => {
   try {
     return new URL(normalizePublishURL(url)).protocol === 'https:';