我已经追踪到了罪魁祸首：discourse-policy，正如 @Vraag 所建议的。与 @Vraag 的说法相反，即使禁用了该插件，它也会影响“消失”的主题：只要它出现在插件列表中，未登录时该主题就会“消失”。
使用 Policy 插件的第一个回复是：Exploring community-based social media - #2 by system - Share - petites singularités
该帖子的 Markdown 内容：
[policy group=trust_level_1 reminder=daily]
我们不使用第三方 Cookie。
[/policy]
以下是错误日志：
TypeError: p is null
Url: https://ps.zoethical.org/assets/plugins/discourse-policy-60b8413b741df408ff16f757f644f9de7cb64099d24c33dc3d85ef735478d72a.js
Line: 1
Column: 3373
Window Location: https://ps.zoethical.org/t/welcome-to-p-s/8
以下是堆栈跟踪：
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