diff --git a/.travis.yml b/.travis.yml
index c13e5f7..b2023cf 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,15 +2,16 @@ language: php
 
 sudo: true
 
+services:
+  - mysql
+
 addons:
   firefox: "47.0.1"
-  postgresql: "9.4"
+  postgresql: "9.5"
   apt:
     packages:
     - openjdk-8-jre
 
-dist: trusty
-
 cache:
   directories:
   - $HOME/.composer/cache
@@ -26,8 +27,6 @@ env:
   - DB=pgsql  MOODLE_BRANCH=MOODLE_38_STABLE
   - DB=pgsql  MOODLE_BRANCH=MOODLE_39_STABLE
   - DB=mysqli MOODLE_BRANCH=MOODLE_39_STABLE
-  - DB=pgsql  MOODLE_BRANCH=master
-  - DB=mysqli MOODLE_BRANCH=master
 
 matrix:
   include:
@@ -37,13 +36,13 @@ matrix:
       env: DB=mysqli MOODLE_BRANCH=MOODLE_35_STABLE
     - php: 7.1
       env: DB=mysqli MOODLE_BRANCH=MOODLE_33_STABLE NODEJS=8
+    - php: 7.4
+      env: DB=mysqli MOODLE_BRANCH=master
+    - php: 7.4
+      env: DB=pgsql MOODLE_BRANCH=master
 
 before_install:
   - export MOODLE_VERSION=$(echo "$MOODLE_BRANCH" | cut -d'_' -f 2)
-  - if [ ${TRAVIS_PHP_VERSION:0:3} == "7.2" ] && [ $DB == "pgsql" ] && [[ "$MOODLE_VERSION" -gt 38 || "$MOODLE_VERSION" == "master" ]] ; then
-      sudo /etc/init.d/postgresql stop;
-      sudo /etc/init.d/postgresql start 9.5;
-    fi
   - phpenv config-rm xdebug.ini
   - if [ "$NODEJS" = 8 ]; then
       nvm install 8.9;
diff --git a/classes/local/controllers/maintenance_static_page_generator.php b/classes/local/controllers/maintenance_static_page_generator.php
index d58e87b..986750a 100644
--- a/classes/local/controllers/maintenance_static_page_generator.php
+++ b/classes/local/controllers/maintenance_static_page_generator.php
@@ -128,7 +128,7 @@ class maintenance_static_page_generator {
                 continue;
             }
             $saved = $this->io->save_url_file($href);
-            if (is_null($saved['url'])) {
+            if (empty($saved['url'])) {
                 $url = $href; // Skipped, use original URL.
             } else {
                 $this->update_link_stylesheet_parse($saved['file'], dirname($href));
diff --git a/classes/local/controllers/maintenance_static_page_io.php b/classes/local/controllers/maintenance_static_page_io.php
index a5dbb40..eeafb53 100644
--- a/classes/local/controllers/maintenance_static_page_io.php
+++ b/classes/local/controllers/maintenance_static_page_io.php
@@ -213,7 +213,7 @@ class maintenance_static_page_io {
     /**
      * Saves the content of the URL into a file, returning the local filename.
      * @param string $url Input URL.
-     * @return string|null Output filename or null if skipped.
+     * @return array|null Output an array with the filename and url or null if skipped.
      */
     public function save_url_file($url) {
         global $CFG;