diff --git a/adminer/include/adminer.inc.php b/adminer/include/adminer.inc.php
index d81a3a71..b21ae673 100644
--- a/adminer/include/adminer.inc.php
+++ b/adminer/include/adminer.inc.php
@@ -125,7 +125,7 @@ class Adminer {
 		echo adminer()->loginFormField('driver', '<tr><th>' . lang('System') . '<td>', html_select("auth[driver]", SqlDriver::$drivers, DRIVER, "loginDriver(this);"));
 		echo adminer()->loginFormField('server', '<tr><th>' . lang('Server') . '<td>', '<input name="auth[server]" value="' . h(SERVER) . '" title="hostname[:port]" placeholder="localhost" autocapitalize="off">');
 		// this is matched by compile.php
-		echo adminer()->loginFormField('username', '<tr><th>' . lang('Username') . '<td>', '<input name="auth[username]" id="username" autofocus value="' . h($_GET["username"]) . '" autocomplete="username" autocapitalize="off">' . script("qs('#username').form['auth[driver]'].onchange();"));
+		echo adminer()->loginFormField('username', '<tr><th>' . lang('Username') . '<td>', '<input name="auth[username]" id="username" autofocus value="' . h($_GET["username"]) . '" autocomplete="username" autocapitalize="off">' . script("const authDriver = qs('#username').form['auth[driver]']; authDriver && authDriver.onchange();"));
 		echo adminer()->loginFormField('password', '<tr><th>' . lang('Password') . '<td>', '<input type="password" name="auth[password]" autocomplete="current-password">');
 		echo adminer()->loginFormField('db', '<tr><th>' . lang('Database') . '<td>', '<input name="auth[db]" value="' . h($_GET["db"]) . '" autocapitalize="off">');
 		echo "</table>\n";
diff --git a/compile.php b/compile.php
index 8948c247..53c2ac38 100755
--- a/compile.php
+++ b/compile.php
@@ -316,7 +316,7 @@ if ($vendor) {
 		if (!$count) {
 			echo "auth[driver] form field not found\n";
 		}
-		$file = str_replace(" . script(\"qs('#username').form['auth[driver]'].onchange();\")", "", $file);
+		$file = str_replace(" . script(\"const authDriver = qs('#username').form['auth[driver]']; authDriver && authDriver.onchange();\")", "", $file);
 		if ($vendor == "sqlite") {
 			$file = str_replace(");\n\t\techo \$this->loginFormField('server', '<tr><th>' . lang('Server') . '<td>', '<input name=\"auth[server]", ' . \'<input type="hidden" name="auth[server]"', $file);
 		}