找到：app/Api/Controller/Threads ListThreadsV2Controller.php

找到:

$cannotViewPosts = !in_array('thread.viewPosts', $permissions);
$cannotFreeViewPosts = !in_array('thread.freeViewPosts.' . $thread['type'], $permissions);

修改为

$cannotViewPosts = !in_array('category'.$thread["category_id"].'.thread.viewPosts', $permissions);
$cannotFreeViewPosts = !in_array('category'.$thread["category_id"].'.thread.freeViewPosts.' . $thread['type'], $permissions);

本方法为临时解决办法，有问题请回帖