diff --git a/lib/navigationlib.php b/lib/navigationlib.php
index 3b2ec783676..dcf6f9314f2 100644
--- a/lib/navigationlib.php
+++ b/lib/navigationlib.php
@@ -1017,7 +1017,21 @@ class navigation_node implements renderable {
                 );
             }
         }
+    }
 
+    /**
+     * Reset all static data.
+     *
+     * @throws coding_exception if called outside of a unit test
+     */
+    public static function reset_all_data(): void {
+        if (!defined('PHPUNIT_TEST') || !PHPUNIT_TEST) {
+            throw new coding_exception('Resetting all data is not allowed outside of PHPUnit tests.');
+        }
+
+        self::$fullmeurl = null;
+        self::$autofindactive = true;
+        self::$loadadmintree = false;
     }
 }
 
diff --git a/lib/phpunit/classes/util.php b/lib/phpunit/classes/util.php
index 3520d19c27f..86b52503aa3 100644
--- a/lib/phpunit/classes/util.php
+++ b/lib/phpunit/classes/util.php
@@ -205,6 +205,7 @@ class phpunit_util extends testing_util {
         // reinitialise following globals
         $OUTPUT = new bootstrap_renderer();
         $PAGE = new moodle_page();
+        \navigation_node::reset_all_data();
         $FULLME = null;
         $ME = null;
         $SCRIPT = null;
diff --git a/lib/phpunit/tests/basic_test.php b/lib/phpunit/tests/basic_test.php
index 0fdb19db168..bb10b9c3471 100644
--- a/lib/phpunit/tests/basic_test.php
+++ b/lib/phpunit/tests/basic_test.php
@@ -377,4 +377,25 @@ STRING;
         $this->assertFalse($DB->is_transaction_started());
         $this->assertEquals($originalname, $DB->get_field('course', 'fullname', ['id' => $COURSE->id]));
     }
+
+    /**
+     * Test that the navigation node URL is overridden correctly.
+     */
+    public function test_set_navigation_url(): void {
+        \navigation_node::override_active_url(new \moodle_url('/foo/bar/baz'));
+        $this->assertNotNull(
+            (new \ReflectionClass(\navigation_node::class))->getStaticPropertyValue('fullmeurl', null),
+        );
+    }
+
+    /**
+     * Test that the after-test teardown correctly resets the navigation node URL.
+     *
+     * @depends test_set_navigation_url
+     */
+    public function test_navigation_url_reset(): void {
+        $this->assertNull(
+            (new \ReflectionClass(\navigation_node::class))->getStaticPropertyValue('fullmeurl', null),
+        );
+    }
 }
diff --git a/lib/tests/navigationlib_test.php b/lib/tests/navigationlib_test.php
index 0c6f48ceb04..c02ad340686 100644
--- a/lib/tests/navigationlib_test.php
+++ b/lib/tests/navigationlib_test.php
@@ -48,6 +48,9 @@ final class navigationlib_test extends \advanced_testcase {
     protected function setup_node() {
         global $PAGE, $SITE;
 
+        // Perform a reset between tests to reset the PAGE.
+        $this->resetAfterTest();
+
         $PAGE->set_url('/');
         $PAGE->set_course($SITE);