diff --git a/client/plugins/format-date-safe.client.js b/client/plugins/format-date-safe.client.js
new file mode 100644
index 000000000..bd11a9569
--- /dev/null
+++ b/client/plugins/format-date-safe.client.js
@@ -0,0 +1,37 @@
+// Wrap app.$formatDate to accept ISO strings / numbers safely
+import Vue from 'vue'
+import { parseISO, isValid } from 'date-fns'
+import format from 'date-fns/format'
+
+export default ({ app }) => {
+  const use = (impl) => (v, p) => {
+    let d = v instanceof Date ? v : null
+    if (!d && typeof v === 'string') {
+      const k = parseISO(v)
+      if (isValid(k)) d = k
+    }
+    if (!d && (typeof v === 'number' || typeof v === 'string')) {
+      const k = new Date(v)
+      if (isValid(k)) d = k
+    }
+    if (!d) return ''
+    try {
+      return impl(d, p)
+    } catch {
+      try {
+        return format(d, p || 'yyyy-MM-dd')
+      } catch {
+        return ''
+      }
+    }
+  }
+  if (typeof app.$formatDate === 'function') {
+    const safe = use((d, p) => app.$formatDate(d, p))
+    app.$formatDate = safe
+    Vue.prototype.$formatDate = safe
+  } else {
+    const safe = use((d, p) => format(d, p || 'yyyy-MM-dd'))
+    app.$formatDate = safe
+    Vue.prototype.$formatDate = safe
+  }
+}