Method: channels.getInactiveChannels
Get inactive channels and supergroups
Return type: messages.InactiveChats
Can bots use this method: NO
MadelineProto Example (now async for huge speed and parallelism!):
if (!file_exists('madeline.php')) {
copy('https://phar.madelineproto.xyz/madeline.php', 'madeline.php');
}
include 'madeline.php';
$MadelineProto = new \danog\MadelineProto\API('session.madeline');
$MadelineProto->start();
$messages_InactiveChats = $MadelineProto->channels->getInactiveChannels();