“顶帖”有什么作用？
The system automatically posts in a topic, which brings it up to the top of the “latest” list. It can be useful for re-surfacing old topics which have not been “solved” yet.
Don’t want to split hairs, but since the question was apparently about “bumping topics” more generally, it’s worth mentioning that the term refers to bringing topics back to the top of latest topics regardless of whether this is done by the system or a human.
tl;dr bumping = resurfacing older topics by posting a new reply, auto-bumping = when this is done by a machine (and, I believe, a rather unique feature of discourse).
What causes the system to bump a topic?
There is a category setting. See Automatically bumping old topics on a category
你好，
在 https://community.hiveeyes.org/ 上，我们希望能偶尔手动置顶某个特定主题（这次是 https://community.hiveeyes.org/t/annapurna-firmware-images-for-pycom-esp32/2754）。
这个功能之前是否讨论过？我们建议在“主题操作”菜单中的“重置置顶日期”按钮附近添加一个选项。
虽然我们知道随时欢迎提交拉取请求（Pull Requests），但我们对 Discourse 的代码库并不太熟悉，因此想在此谦卑地提出请求，希望能得到机会。
祝一切顺利，保持热情！
此致，
Andreas。
设置主题计时器应该可以为您做到这一点。
或者，如果你只是想“偶尔”手动“特别”地顶一下某个“特定”话题，不也可以发个帖子吗？
您也可以先发布帖子，然后将其删除，这就是俗称的“幽灵顶帖”。例如，垃圾信息偶尔会绕过我们的初步检查和 Akismet 的过滤——值得庆幸的是，这种情况非常罕见！