diff --git a/admin/tool/behat/cli/util_single_run.php b/admin/tool/behat/cli/util_single_run.php
index 42b335cc8cb..868dd84b3e5 100644
--- a/admin/tool/behat/cli/util_single_run.php
+++ b/admin/tool/behat/cli/util_single_run.php
@@ -187,10 +187,13 @@ if ($options['install']) {
     behat_config_manager::set_behat_run_config_value('axe', $options['axe']);
 
     // Enable test mode.
+    $timestart = microtime(true);
+    mtrace('Creating Behat configuration ...', '');
     behat_util::start_test_mode($options['add-core-features-to-theme'], $options['optimize-runs'], $parallel, $run);
+    mtrace(' done in ' . round(microtime(true) - $timestart, 2) . ' seconds.');
 
     // Themes are only built in the 'enable' command.
-    behat_util::build_themes();
+    behat_util::build_themes(true);
     mtrace("Testing environment themes built");
 
     // This is only displayed once for parallel install.
diff --git a/lib/behat/classes/util.php b/lib/behat/classes/util.php
index aff5dcf6322..feaf4e67280 100644
--- a/lib/behat/classes/util.php
+++ b/lib/behat/classes/util.php
@@ -135,7 +135,7 @@ class behat_util extends testing_util {
     /**
      * Build theme CSS.
      */
-    public static function build_themes() {
+    public static function build_themes($mtraceprogress = false) {
         global $CFG;
         require_once("{$CFG->libdir}/outputlib.php");
 
@@ -147,7 +147,7 @@ class behat_util extends testing_util {
         }, $themenames);
 
         // Build the list of themes and cache them in local cache.
-        $themes = theme_build_css_for_themes($themeconfigs, ['ltr'], true);
+        $themes = theme_build_css_for_themes($themeconfigs, ['ltr'], true, $mtraceprogress);
 
         $framework = self::get_framework();
         $storageroot = self::get_dataroot() . "/{$framework}/themedata";
@@ -278,7 +278,6 @@ class behat_util extends testing_util {
      * @return void
      */
     public static function start_test_mode($themesuitewithallfeatures = false, $tags = '', $parallelruns = 0, $run = 0) {
-        global $CFG;
 
         if (!defined('BEHAT_UTIL')) {
             throw new coding_exception('This method can be only used by Behat CLI tool');
diff --git a/lib/outputlib.php b/lib/outputlib.php
index 6b22cfcf07c..9f533ca84d4 100644
--- a/lib/outputlib.php
+++ b/lib/outputlib.php
@@ -181,7 +181,8 @@ function theme_get_css_filename($themename, $globalrevision, $themerevision, $di
  * @param bool           $cache        Should the generated files be stored in local cache.
  * @return array         The built theme content in a multi-dimensional array of name => direction => content
  */
-function theme_build_css_for_themes($themeconfigs = [], $directions = ['rtl', 'ltr'], $cache = true): array {
+function theme_build_css_for_themes($themeconfigs = [], $directions = ['rtl', 'ltr'],
+        $cache = true, $mtraceprogress = false): array {
     global $CFG;
 
     if (empty($themeconfigs)) {
@@ -202,6 +203,11 @@ function theme_build_css_for_themes($themeconfigs = [], $directions = ['rtl', 'l
 
         // First generate all the new css.
         foreach ($directions as $direction) {
+            if ($mtraceprogress) {
+                $timestart = microtime(true);
+                mtrace('Building theme CSS for ' . $themeconfig->name . ' [' .
+                        $direction . '] ...', '');
+            }
             // Lock it on. Technically we should build all themes for SVG and no SVG - but ie9 is out of support.
             $themeconfig->force_svg_use(true);
             $themeconfig->set_rtl_mode(($direction === 'rtl'));
@@ -212,6 +218,9 @@ function theme_build_css_for_themes($themeconfigs = [], $directions = ['rtl', 'l
                 $filename = theme_get_css_filename($themeconfig->name, $themerev, $newrevision, $direction);
                 css_store_css($themeconfig, $filename, $themecss[$direction]);
             }
+            if ($mtraceprogress) {
+                mtrace(' done in ' . round(microtime(true) - $timestart, 2) . ' seconds.');
+            }
         }
         $themescss[$themeconfig->name] = $themecss;