[BUGFIX] The placeholders of the mail subject aren't replaced

Classes/Service/MailTemplateService.php

@@ -697,12 +697,21 @@ class MailTemplateService {
 		$emailView->assignMultiple($this->markers);
 		$emailView->assign('all_fields', $this->getAllMarker($this->markers));
 
+		$overwrittenEmailBody = $this->getOverwrittenEmailBody();
+		$overwrittenSubject = '';
+		if ($this->subject !== '' && $this->subject !== NULL) {
+			$overwrittenSubject = $this->subject;
+		}
+
 		if ($template !== NULL) {
-			$emailView->setTemplateSource(\trim($template->getSubject()));
+			$emailView->setTemplateSource(
+				\trim(empty($overwrittenSubject) ? $template->getSubject() : $overwrittenSubject)
+			);
 			$subject = $emailView->render();
 
-			$overwrittenEmailBody = $this->getOverwrittenEmailBody();
-			$emailView->setTemplateSource(empty($overwrittenEmailBody) ? $template->getContent() : $overwrittenEmailBody);
+			$emailView->setTemplateSource(
+				empty($overwrittenEmailBody) ? $template->getContent() : $overwrittenEmailBody
+			);
 		} else {
 			$subject = $registerService->getRegisterArray()[$this->extensionKey][$this->templateName]['subject'];
 			if (\is_array($subject)) {
@@ -711,18 +720,13 @@ class MailTemplateService {
 					[$this->extensionKey][$this->templateName]['subject'][$this->language]
 				);
 			}
-			if ($subject === NULL && $this->subject !== NULL) {
-				$subject = $this->subject;
-			}
-			if ($subject !== NULL) {
-				$emailView->setTemplateSource($subject);
-				$subject = $emailView->render();
-			}
-			$emailView->setTemplateSource(empty($overwrittenEmailBody) ? $defaultTemplateContent : $overwrittenEmailBody);
-		}
 
-		if ($this->subject !== '' && $this->subject !== NULL) {
-			$subject = $this->subject;
+			$emailView->setTemplateSource(empty($overwrittenSubject) ? $subject : $overwrittenSubject);
+			$subject = $emailView->render();
+
+			$emailView->setTemplateSource(
+				empty($overwrittenEmailBody) ? $defaultTemplateContent : $overwrittenEmailBody
+			);
 		}
 
 		$this->mailMessage->setSubject($subject);