> For the complete documentation index, see [llms.txt](https://overleaf-pro.ayaka.space/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overleaf-pro.ayaka.space/latex/zh-cn/zhi-shi-ku/163-why-does-it-sometimes-take-a-lot-of-time-to-show-the-pdf-preview.md).

# 为什么有时显示 PDF 预览会花很长时间？

这可能是由于你正在处理的文档中存在错误——只有当文档能够成功编译时，预览才会更新。因此，任何错误都会阻止预览更新，在错误被修正之前，它将继续显示上一次成功编译的结果。

你可以将鼠标移到预览右上角的“error”一词上，查看文档中的任何错误。例如，一个常见错误是需要将数学符号放在美元符号中，例如 $$\phi$$ 而不是直接写 \phi。

如果即使错误已解决，PDF 预览仍未更新，请 [告诉我们](https://www.overleaf.com/contact) 我们会帮你查看。


---

# Agent Instructions
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## Querying This Documentation
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