diff --git a/mod/forum/lib.php b/mod/forum/lib.php
index 4940d41672c..cb0bbbbcef9 100644
--- a/mod/forum/lib.php
+++ b/mod/forum/lib.php
@@ -1602,27 +1602,34 @@ function forum_print_recent_activity($course, $viewfullnames, $timestart) {
     }
 
     echo $OUTPUT->heading(get_string('newforumposts', 'forum').':', 3);
-    echo "\n<ul class='unlist'>\n";
+    $list = html_writer::start_tag('ul', ['class' => 'unlist']);
 
     foreach ($printposts as $post) {
         $subjectclass = empty($post->parent) ? ' bold' : '';
+        $authorhidden = forum_is_author_hidden($post, (object) ['type' => $post->forumtype]);
 
-        echo '<li><div class="head">'.
-               '<div class="date">'.userdate($post->modified, $strftimerecent).'</div>'.
-               '<div class="name">'.fullname($post, $viewfullnames).'</div>'.
-             '</div>';
-        echo '<div class="info'.$subjectclass.'">';
-        if (empty($post->parent)) {
-            echo '"<a href="'.$CFG->wwwroot.'/mod/forum/discuss.php?d='.$post->discussion.'">';
-        } else {
-            echo '"<a href="'.$CFG->wwwroot.'/mod/forum/discuss.php?d='.$post->discussion.'&amp;parent='.$post->parent.'#p'.$post->id.'">';
+        $list .= html_writer::start_tag('li');
+        $list .= html_writer::start_div('head');
+        $list .= html_writer::div(userdate($post->modified, $strftimerecent), 'date');
+        if (!$authorhidden) {
+            $list .= html_writer::div(fullname($post, $viewfullnames), 'name');
+        }
+        $list .= html_writer::end_div(); // Head.
+
+        $list .= html_writer::start_div('info' . $subjectclass);
+        $discussionurl = new moodle_url('/mod/forum/discuss.php', ['d' => $post->discussion]);
+        if (!empty($post->parent)) {
+            $discussionurl->param('parent', $post->parent);
+            $discussionurl->set_anchor('p'. $post->id);
         }
         $post->subject = break_up_long_words(format_string($post->subject, true));
-        echo $post->subject;
-        echo "</a>\"</div></li>\n";
+        $list .= html_writer::link($discussionurl, $post->subject);
+        $list .= html_writer::end_div(); // Info.
+        $list .= html_writer::end_tag('li');
     }
 
-    echo "</ul>\n";
+    $list .= html_writer::end_tag('ul');
+    echo $list;
 
     return true;
 }
@@ -3319,53 +3326,69 @@ function forum_print_post($post, $discussion, $forum, &$cm, $course, $ownpost=fa
         $forumpostclass .= ' lastpost';
     }
 
+    // Flag to indicate whether we should hide the author or not.
+    $authorhidden = forum_is_author_hidden($post, $forum);
     $postbyuser = new stdClass;
     $postbyuser->post = $post->subject;
     $postbyuser->user = $postuser->fullname;
     $discussionbyuser = get_string('postbyuser', 'forum', $postbyuser);
     $output .= html_writer::tag('a', '', array('id'=>'p'.$post->id));
-    $output .= html_writer::start_tag('div', array('class'=>'forumpost clearfix'.$forumpostclass.$topicclass,
-                                                   'role' => 'region',
-                                                   'aria-label' => $discussionbyuser));
-    $output .= html_writer::start_tag('div', array('class'=>'row header clearfix'));
-    $output .= html_writer::start_tag('div', array('class'=>'left picture'));
-    $output .= $OUTPUT->user_picture($postuser, array('courseid'=>$course->id));
-    $output .= html_writer::end_tag('div');
+    // Begin forum post.
+    $output .= html_writer::start_div('forumpost clearfix' . $forumpostclass . $topicclass,
+        ['role' => 'region', 'aria-label' => $discussionbyuser]);
+    // Begin header row.
+    $output .= html_writer::start_div('row header clearfix');
 
+    // User picture.
+    if (!$authorhidden) {
+        $picture = $OUTPUT->user_picture($postuser, ['courseid' => $course->id]);
+        $output .= html_writer::div($picture, 'left picture');
+        $topicclass = 'topic' . $topicclass;
+    }
 
-    $output .= html_writer::start_tag('div', array('class'=>'topic'.$topicclass));
-
+    // Begin topic column.
+    $output .= html_writer::start_div($topicclass);
     $postsubject = $post->subject;
     if (empty($post->subjectnoformat)) {
         $postsubject = format_string($postsubject);
     }
-    $output .= html_writer::tag('div', $postsubject, array('class'=>'subject',
-                                                           'role' => 'heading',
-                                                           'aria-level' => '2'));
+    $output .= html_writer::div($postsubject, 'subject', ['role' => 'heading', 'aria-level' => '2']);
 
-    $by = new stdClass();
-    $by->name = html_writer::link($postuser->profilelink, $postuser->fullname);
-    $by->date = userdate($post->modified);
-    $output .= html_writer::tag('div', get_string('bynameondate', 'forum', $by), array('class'=>'author',
-                                                                                       'role' => 'heading',
-                                                                                       'aria-level' => '2'));
-
-    $output .= html_writer::end_tag('div'); //topic
-    $output .= html_writer::end_tag('div'); //row
-
-    $output .= html_writer::start_tag('div', array('class'=>'row maincontent clearfix'));
-    $output .= html_writer::start_tag('div', array('class'=>'left'));
-
-    $groupoutput = '';
-    if ($groups) {
-        $groupoutput = print_group_picture($groups, $course->id, false, true, true);
+    if ($authorhidden) {
+        $bytext = userdate($post->modified);
+    } else {
+        $by = new stdClass();
+        $by->date = userdate($post->modified);
+        $by->name = html_writer::link($postuser->profilelink, $postuser->fullname);
+        $bytext = get_string('bynameondate', 'forum', $by);
+    }
+    $bytextoptions = [
+        'role' => 'heading',
+        'aria-level' => '2',
+    ];
+    $output .= html_writer::div($bytext, 'author', $bytextoptions);
+    // End topic column.
+    $output .= html_writer::end_div();
+
+    // End header row.
+    $output .= html_writer::end_div();
+
+    // Row with the forum post content.
+    $output .= html_writer::start_div('row maincontent clearfix');
+    // Show if author is not hidden or we have groups.
+    if (!$authorhidden || $groups) {
+        $output .= html_writer::start_div('left');
+        $groupoutput = '';
+        if ($groups) {
+            $groupoutput = print_group_picture($groups, $course->id, false, true, true);
+        }
+        if (empty($groupoutput)) {
+            $groupoutput = '&nbsp;';
+        }
+        $output .= html_writer::div($groupoutput, 'grouppictures');
+        $output .= html_writer::end_div(); // Left side.
     }
-    if (empty($groupoutput)) {
-        $groupoutput = '&nbsp;';
-    }
-    $output .= html_writer::tag('div', $groupoutput, array('class'=>'grouppictures'));
 
-    $output .= html_writer::end_tag('div'); //left side
     $output .= html_writer::start_tag('div', array('class'=>'no-overflow'));
     $output .= html_writer::start_tag('div', array('class'=>'content'));
 
@@ -5899,6 +5922,7 @@ function forum_get_recent_mod_activity(&$activities, &$index, $timestart, $cours
         $tmpactivity->content->discussion = $post->discussion;
         $tmpactivity->content->subject    = format_string($post->subject);
         $tmpactivity->content->parent     = $post->parent;
+        $tmpactivity->content->forumtype  = $post->forumtype;
 
         $tmpactivity->user = new stdClass();
         $additionalfields = array('id' => 'userid', 'picture', 'imagealt', 'email');
@@ -5913,48 +5937,85 @@ function forum_get_recent_mod_activity(&$activities, &$index, $timestart, $cours
 }
 
 /**
- * @todo Document this function
- * @global object
+ * Outputs the forum post indicated by $activity.
+ *
+ * @param object $activity      the activity object the forum resides in
+ * @param int    $courseid      the id of the course the forum resides in
+ * @param bool   $detail        not used, but required for compatibilty with other modules
+ * @param int    $modnames      not used, but required for compatibilty with other modules
+ * @param bool   $viewfullnames not used, but required for compatibilty with other modules
  */
 function forum_print_recent_mod_activity($activity, $courseid, $detail, $modnames, $viewfullnames) {
-    global $CFG, $OUTPUT;
+    global $OUTPUT;
 
-    if ($activity->content->parent) {
+    $content = $activity->content;
+    if ($content->parent) {
         $class = 'reply';
     } else {
         $class = 'discussion';
     }
 
-    echo '<table border="0" cellpadding="3" cellspacing="0" class="forum-recent">';
+    $tableoptions = [
+        'border' => '0',
+        'cellpadding' => '3',
+        'cellspacing' => '0',
+        'class' => 'forum-recent'
+    ];
+    $output = html_writer::start_tag('table', $tableoptions);
+    $output .= html_writer::start_tag('tr');
 
-    echo "<tr><td class=\"userpicture\" valign=\"top\">";
-    echo $OUTPUT->user_picture($activity->user, array('courseid'=>$courseid));
-    echo "</td><td class=\"$class\">";
+    $post = (object) ['parent' => $content->parent];
+    $forum = (object) ['type' => $content->forumtype];
+    $authorhidden = forum_is_author_hidden($post, $forum);
 
-    if ($activity->content->parent) {
+    // Show user picture if author should not be hidden.
+    if (!$authorhidden) {
+        $pictureoptions = [
+            'courseid' => $courseid,
+            'link' => $authorhidden,
+            'alttext' => $authorhidden,
+        ];
+        $picture = $OUTPUT->user_picture($activity->user, $pictureoptions);
+        $output .= html_writer::tag('td', $picture, ['class' => 'userpicture', 'valign' => 'top']);
+    }
+
+    // Discussion title and author.
+    $output .= html_writer::start_tag('td', ['class' => $class]);
+    if ($content->parent) {
         $class = 'title';
     } else {
         // Bold the title of new discussions so they stand out.
         $class = 'title bold';
     }
-    echo "<div class=\"{$class}\">";
+
+    $output .= html_writer::start_div($class);
     if ($detail) {
         $aname = s($activity->name);
-        echo "<img src=\"" . $OUTPUT->pix_url('icon', $activity->type) . "\" ".
-             "class=\"icon\" alt=\"{$aname}\" />";
+        $output .= html_writer::img($OUTPUT->pix_url('icon', $activity->type), $aname, ['class' => 'icon']);
     }
-    echo "<a href=\"$CFG->wwwroot/mod/forum/discuss.php?d={$activity->content->discussion}"
-         ."#p{$activity->content->id}\">{$activity->content->subject}</a>";
-    echo '</div>';
+    $discussionurl = new moodle_url('/mod/forum/discuss.php', ['d' => $content->discussion]);
+    $discussionurl->set_anchor('p' . $activity->content->id);
+    $output .= html_writer::link($discussionurl, $content->subject);
+    $output .= html_writer::end_div();
 
-    echo '<div class="user">';
-    $fullname = fullname($activity->user, $viewfullnames);
-    echo "<a href=\"$CFG->wwwroot/user/view.php?id={$activity->user->id}&amp;course=$courseid\">"
-         ."{$fullname}</a> - ".userdate($activity->timestamp);
-    echo '</div>';
-      echo "</td></tr></table>";
+    $timestamp = userdate($activity->timestamp);
+    if ($authorhidden) {
+        $authornamedate = $timestamp;
+    } else {
+        $fullname = fullname($activity->user, $viewfullnames);
+        $userurl = new moodle_url('/user/view.php');
+        $userurl->params(['id' => $activity->user->id, 'course' => $courseid]);
+        $by = new stdClass();
+        $by->name = html_writer::link($userurl, $fullname);
+        $by->date = $timestamp;
+        $authornamedate = get_string('bynameondate', 'forum', $by);
+    }
+    $output .= html_writer::div($authornamedate, 'user');
+    $output .= html_writer::end_tag('td');
+    $output .= html_writer::end_tag('tr');
+    $output .= html_writer::end_tag('table');
 
-    return;
+    echo $output;
 }
 
 /**
@@ -7910,3 +7971,24 @@ function mod_forum_myprofile_navigation(core_user\output\myprofile\tree $tree, $
 
     return true;
 }
+
+/**
+ * Checks whether the author's name and picture for a given post should be hidden or not.
+ *
+ * @param object $post The forum post.
+ * @param object $forum The forum object.
+ * @return bool
+ * @throws coding_exception
+ */
+function forum_is_author_hidden($post, $forum) {
+    if (!isset($post->parent)) {
+        throw new coding_exception('$post->parent must be set.');
+    }
+    if (!isset($forum->type)) {
+        throw new coding_exception('$forum->type must be set.');
+    }
+    if ($forum->type === 'single' && empty($post->parent)) {
+        return true;
+    }
+    return false;
+}
diff --git a/mod/forum/tests/lib_test.php b/mod/forum/tests/lib_test.php
index cf29d4f5c8b..8e551a584d3 100644
--- a/mod/forum/tests/lib_test.php
+++ b/mod/forum/tests/lib_test.php
@@ -3012,6 +3012,39 @@ class mod_forum_lib_testcase extends advanced_testcase {
         $this->assertCount($expectedreplycount, $unmailed);
     }
 
+    /**
+     * Test for forum_is_author_hidden.
+     */
+    public function test_forum_is_author_hidden() {
+        // First post, different forum type.
+        $post = (object) ['parent' => 0];
+        $forum = (object) ['type' => 'standard'];
+        $this->assertFalse(forum_is_author_hidden($post, $forum));
+
+        // Child post, different forum type.
+        $post->parent = 1;
+        $this->assertFalse(forum_is_author_hidden($post, $forum));
+
+        // First post, single simple discussion forum type.
+        $post->parent = 0;
+        $forum->type = 'single';
+        $this->assertTrue(forum_is_author_hidden($post, $forum));
+
+        // Child post, single simple discussion forum type.
+        $post->parent = 1;
+        $this->assertFalse(forum_is_author_hidden($post, $forum));
+
+        // Incorrect parameters: $post.
+        $this->setExpectedException('coding_exception', '$post->parent must be set.');
+        unset($post->parent);
+        forum_is_author_hidden($post, $forum);
+
+        // Incorrect parameters: $forum.
+        $this->setExpectedException('coding_exception', '$forum->type must be set.');
+        unset($forum->type);
+        forum_is_author_hidden($post, $forum);
+    }
+
     public function forum_get_unmailed_posts_provider() {
         return [
             'Untimed discussion; Single post; maxeditingtime not expired' => [