From 0905fd4536240d925dff5fd9f923c0dd27c1fd8d Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Wed, 29 Sep 2021 11:04:10 +0200
Subject: [PATCH] Merge pull request #5217 from
 overleaf/jpa-web-templates-de-ng

[web] de-ng templates module (server-pro)

GitOrigin-RevId: 8d2ffd6a109d61b11d6d7c1acb781b429da3891c
---
 .../frontend/js/features/fallback-image/index.js | 16 ++++++++++++++++
 services/web/frontend/js/marketing.js            |  2 ++
 2 files changed, 18 insertions(+)
 create mode 100644 services/web/frontend/js/features/fallback-image/index.js

diff --git a/services/web/frontend/js/features/fallback-image/index.js b/services/web/frontend/js/features/fallback-image/index.js
new file mode 100644
index 0000000000..8ab3ab5003
--- /dev/null
+++ b/services/web/frontend/js/features/fallback-image/index.js
@@ -0,0 +1,16 @@
+function loadingFailed(imgEl) {
+  return imgEl.complete && imgEl.naturalWidth === 0
+}
+
+document.querySelectorAll('[data-ol-fallback-image]').forEach(imgEl => {
+  function showFallback() {
+    imgEl.src = imgEl.getAttribute('data-ol-fallback-image')
+  }
+  if (loadingFailed(imgEl)) {
+    // The image loading failed before the sprinkle ran.
+    showFallback()
+  } else {
+    // The image loading might fail in the future.
+    imgEl.addEventListener('error', showFallback)
+  }
+})
diff --git a/services/web/frontend/js/marketing.js b/services/web/frontend/js/marketing.js
index 8aa97e710e..6c9be38316 100644
--- a/services/web/frontend/js/marketing.js
+++ b/services/web/frontend/js/marketing.js
@@ -5,6 +5,8 @@ import './features/form-helpers/hydrate-form'
 import './features/link-helpers/slow-link'
 import './features/contact-form'
 import './features/event-tracking'
+import './features/fallback-image'
 import './features/multi-submit'
 
 $('[data-ol-lang-selector-tooltip]').tooltip({ trigger: 'hover' })
+$('[data-toggle="tooltip"]').tooltip()