diff --git a/CHANGES.md b/CHANGES.md
index 69f74aaa996cf920ec4a1d6475028ac579513664..d8dabfa59fcce719f6c07bd7843000a575c30c47 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -4,6 +4,10 @@ moodle-theme_boost_campus
 Changes
 -------
 
+### Unreleased
+
+* 2020-11-18 - Improvement: Declare which major stable version of Moodle this plugin supports (see MDL-59562 for details).
+
 ### Release v3.9-r3
 
 * 2020-11-18 - Bugfix: Fixed another regression when showing description border for restricted activities.
diff --git a/version.php b/version.php
index e5e6f12e8cfb6febc2cd579f58a9ab4b4de3a5f7..afc2cc893ac51e31b51b71551b32232a15d6cc20 100644
--- a/version.php
+++ b/version.php
@@ -28,5 +28,6 @@ $plugin->component = 'theme_boost_campus';
 $plugin->version = 2020112300;
 $plugin->release = 'v3.9-r3';
 $plugin->requires = 2020061502;
+$plugin->supported = [39, 39];
 $plugin->maturity = MATURITY_STABLE;
 $plugin->dependencies = array('theme_boost' => 2020061500);