[TASK] Dont send preview emails

Classes/Service/MailTemplateService.php

@@ -389,16 +389,21 @@ class MailTemplateService {
 			$this->mailMessage->send();
 			$dateTime = new DateTime();
 			$currentTimestamp = $dateTime->getTimestamp();
-			$this->addMailToMailQueue(
-				$this->extensionKey, $this->templateName, $subject, $emailBody, $this->priority,
-				$currentTimestamp, TRUE, $currentTimestamp, $this->language, $siteRootId
-			);
+
+			if (!$isPreview) {
+				$this->addMailToMailQueue(
+					$this->extensionKey, $this->templateName, $subject, $emailBody, $this->priority,
+					$currentTimestamp, TRUE, $currentTimestamp, $this->language, $siteRootId
+				);
+			}
 
 		} else {
-			$this->addMailToMailQueue(
-				$this->extensionKey, $this->templateName, $subject, $emailBody, $this->priority, 0, FALSE, 0,
-				$this->language, $siteRootId
-			);
+			if (!$isPreview) {
+				$this->addMailToMailQueue(
+					$this->extensionKey, $this->templateName, $subject, $emailBody, $this->priority, 0, FALSE, 0,
+					$this->language, $siteRootId
+				);
+			}
 		}
 
 		return TRUE;