Very basic email subject customization

server/notification-providers/smtp.js

@@ -20,6 +20,14 @@ class SMTP extends NotificationProvider {
                 pass: notification.smtpPassword,
             };
         }
+        // Lets start with default subject
+        let subject = msg;
+        // Our subject cannot end with whitespace it's often raise spam score
+        let customsubject = notification.customsubject.trim()
+        // If custom subject is not empty, change subject for notification
+        if (customsubject !== "") {
+            subject = customsubject
+        }
 
         let transporter = nodemailer.createTransport(config);
 
@@ -34,7 +42,7 @@ class SMTP extends NotificationProvider {
             cc: notification.smtpCC,
             bcc: notification.smtpBCC,
             to: notification.smtpTo,
-            subject: msg,
+            subject: subject,
             text: bodyTextContent,
             tls: {
                 rejectUnauthorized: notification.smtpIgnoreTLSError || false,

src/components/notifications/SMTP.vue

@@ -43,6 +43,11 @@
         </div>
     </div>
 
+    <div class="mb-3">
+        <label for="subject-email" class="form-label">{{ $t("Custom Email subject") }}</label>
+        <input id="subject-email" v-model="$parent.notification.customsubject" type="text" class="form-control" autocomplete="false" placeholder="[Uptime Kuma] Service status has changed">
+    </div>
+
     <div class="mb-3">
         <label for="to-email" class="form-label">{{ $t("To Email") }}</label>
         <input id="to-email" v-model="$parent.notification.smtpTo" type="text" class="form-control" autocomplete="false" placeholder="example2@kuma.pet, example3@kuma.pet" :required="!hasRecipient">

src/languages/en.js

@@ -201,6 +201,7 @@ export default {
     secureOptionTLS: "TLS (465)",
     "Ignore TLS Error": "Ignore TLS Error",
     "From Email": "From Email",
+    "Custom Email subject": "Custom Email Subject (leave blank for default one)",
     "To Email": "To Email",
     smtpCC: "CC",
     smtpBCC: "BCC",