MyBB Community Forums

In global.php, I found this:

// Set and load the language
if($mybb->input['language'] && $lang->language_exists($mybb->input['language']))
{
	$mybb->settings['bblanguage'] = $mybb->input['language'];
	// If user is logged in, update their language selection with the new one
	if($mybb->user['uid'])
	{
		$db->update_query("users", array("language" => $db->escape_string($mybb->settings['bblanguage'])), "uid='{$mybb->user['uid']}'");
	}
	// Guest = cookie
	else
	{
		my_setcookie("mybblang", $mybb->settings['bblang']);
	}
}
// Cookied language!
else if($mybb->cookies['mybblang'] && $lang->language_exists($mybb->cookies['mybblang']))
{
	$mybb->settings['bblanguage'] = $mybb->input['language'];
}
else if(!isset($mybb->settings['bblanguage']))
{
	$mybb->settings['bblanguage'] = "english";
}

This means the selected language will never be cookied.

It has to be:

// Set and load the language
if($mybb->input['language'] && $lang->language_exists($mybb->input['language']))
{
	$mybb->settings['bblanguage'] = $mybb->input['language'];
	// If user is logged in, update their language selection with the new one
	if($mybb->user['uid'])
	{
		$db->update_query("users", array("language" => $db->escape_string($mybb->settings['bblanguage'])), "uid='{$mybb->user['uid']}'");
	}
	// Guest = cookie
	else
	{
		my_setcookie("mybblang", $mybb->settings['bblanguage']);
	}
}
// Cookied language!
else if($mybb->cookies['mybblang'] && $lang->language_exists($mybb->cookies['mybblang']))
{
	$mybb->settings['bblanguage'] = $mybb->cookies['mybblang'];
}
else if(!isset($mybb->settings['bblanguage']))
{
	$mybb->settings['bblanguage'] = "english";
}

Thank you for your bug report.

This bug has been fixed in our internal code repository. Please note that the problem will not be fixed here until these forums are updated.