Fix issue for when an assignment text has no paragraph tag

client/src/components/content-blocks/assignment/Assignment.vue

@@ -9,7 +9,7 @@
       class="assignment__main-text assignment-text"
       data-cy="assignment-main-text"
       v-if="assignment.assignment > ''"
-      v-html="assignment.assignment"
+      v-html="assignmentHtml"
     />
 
     <assignment-solution
@@ -211,6 +211,19 @@ const feedbackText = computed(() => {
   let sanitizedFeedbackText = sanitize(feedback.text);
   return `<span class="inline-title">Feedback von ${feedback.teacher.firstName} ${feedback.teacher.lastName}:</span> ${sanitizedFeedbackText}`;
 });
+const containsParagraphs = (str: string) => {
+  const parser = new DOMParser();
+  const doc = parser.parseFromString(str, 'text/html');
+  return doc.querySelectorAll('p') > 0;
+};
+const assignmentHtml = computed(() => {
+  const assignmentText = assignment.value.assignment;
+  if (containsParagraphs(assignmentText)) {
+    return assignmentText;
+  }
+  // text needs to be inside a paragraph, otherwise the highlighting will fail
+  return `<p>${assignmentText}</p>`;
+});
 
 const childElements = computed(() => {
   // todo: refactor and merge with the one in ContentComponent.vue