diff --git a/.travis.yml b/.travis.yml
index 109fc31..1112deb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,56 +1,32 @@
 language: php
 
-sudo: true
+dist: trusty
 
 addons:
   apt:
     packages:
       - tidy
 
-php:
-  - 5.4
-  - 5.5
-
-before_install:
-  - pip install --user codecov
-
-env:
-  global:
-    - DB=MYSQL CORE_RELEASE=3.5
-    - MODULE_PATH=comments
-
-    # Set to 1 in the matrix to enable code coverage
-    - COVERAGE=0
-
 matrix:
   include:
-    - php: 5.6
-      #CommentsListTest breaks with this env: DB=MYSQL CORE_RELEASE=3.2 COVERAGE=1
-      env: DB=SQLITE CORE_RELEASE=3.5 COVERAGE=1
-    - php: 7.1
+    - php: '5.6'
       env: DB=MYSQL CORE_RELEASE=3.6
-    - php: 5.6
-      env: DB=PGSQL CORE_RELEASE=3.5
-    - php: 7.1
-      env: DB=MYSQL CORE_RELEASE=3
+    - php: '7.0'
+      env: DB=MYSQL CORE_RELEASE=3.7
+    - php: '7.1'
+      env: DB=PGSQL CORE_RELEASE=3.7
+    - php: '7.2'
+      env: DB=MYSQL CORE_RELEASE=3.7
+    - php: '7.3'
+      env: DB=MYSQL CORE_RELEASE=3.7
 
 before_script:
   - phpenv rehash
   - composer self-update || true
-  - git clone git://github.com/silverstripe-labs/silverstripe-travis-support.git ~/travis-support
+  - git clone git://github.com/silverstripe/silverstripe-travis-support.git ~/travis-support
   # Install suggested modules in order to maximize test coverage
   - php ~/travis-support/travis_setup.php --source `pwd` --target ~/builds/ss --require "ezyang/htmlpurifier:4.*,silverstripe/cms:~3.1"
   - cd ~/builds/ss
 
 script:
-  # Execute tests with no coverage.  This is the fastest option
-  - "if [ \"$COVERAGE\" = \"0\" ]; then vendor/bin/phpunit $MODULE_PATH/tests/; fi"
-
-  # Execute tests with coverage.  Do this for a small
-  - "if [ \"$COVERAGE\" = \"1\" ]; then vendor/bin/phpunit --coverage-clover=coverage.clover $MODULE_PATH/tests/; fi"
-
-after_script:
-    - "if [ \"$COVERAGE\" = \"1\" ]; then mv coverage.clover ~/build/$TRAVIS_REPO_SLUG/; fi"
-    - cd ~/build/$TRAVIS_REPO_SLUG
-    - wget https://scrutinizer-ci.com/ocular.phar
-    - "if [ \"$COVERAGE\" = \"1\" ]; then travis_retry codecov && travis_retry php ocular.phar code-coverage:upload --format=php-clover coverage.clover; fi"
+  - vendor/bin/phpunit comments/tests
diff --git a/code/model/Comment.php b/code/model/Comment.php
index b79282b..2bfb0cf 100755
--- a/code/model/Comment.php
+++ b/code/model/Comment.php
@@ -649,8 +649,10 @@ class Comment extends DataObject
      */
     public function purifyHtml($dirtyHtml)
     {
-        $purifier = $this->getHtmlPurifierService();
-        return $purifier->purify($dirtyHtml);
+        if ($service = $this->getHtmlPurifierService()) {
+            return $service->purify($dirtyHtml);
+        }
+        return $dirtyHtml;
     }
 
     /**
@@ -658,6 +660,10 @@ class Comment extends DataObject
      */
     public function getHtmlPurifierService()
     {
+        if (!class_exists('HTMLPurifier_Config')) {
+            return null;
+        }
+
         $config = HTMLPurifier_Config::createDefault();
         $allowedElements = $this->getOption('html_allowed_elements');
         $config->set('HTML.AllowedElements', $allowedElements);
diff --git a/composer.json b/composer.json
index 97582ac..74993d8 100644
--- a/composer.json
+++ b/composer.json
@@ -22,7 +22,7 @@
         "silverstripe/cms": "The SilverStripe Content Management System"
     },
     "require-dev": {
-        "phpunit/PHPUnit": "~3.7@stable"
+        "phpunit/phpunit": "^5.7"
     },
     "extra": {
         "branch-alias": {
diff --git a/javascript/CommentsInterface.js b/javascript/CommentsInterface.js
index 255b517..5d2d0c0 100755
--- a/javascript/CommentsInterface.js
+++ b/javascript/CommentsInterface.js
@@ -168,8 +168,8 @@
 						comment.fadeOut(1000, function() {
                             comment.remove();
 
-							if(commentsList.children().length === 0) {
-								noCommentsYet.show();
+							if($('.comments-holder .comments-list').children().length === 0) {
+								$('.no-comments-yet').show();
 							}
 						});
 					}
diff --git a/tests/CommentsTest.php b/tests/CommentsTest.php
index 07c8d84..cc8ee30 100644
--- a/tests/CommentsTest.php
+++ b/tests/CommentsTest.php
@@ -974,6 +974,11 @@ class CommentsTest extends FunctionalTest
 
     public function testPurifyHtml()
     {
+        if (!class_exists('HTMLPurifier_Config')) {
+            $this->markTestSkipped('HTMLPurifier class not found');
+            return;
+        }
+
         $comment = $this->objFromFixture('Comment', 'firstComA');
 
         $dirtyHTML = '<p><script>alert("w00t")</script>my comment</p>';