Improve display of charts in export pdf and preview mode

[mustakshif]

Is there an existing issue for this?

• I have searched the existing issues

Can the issue be reproduced with the default theme (daylight/midnight)?

• I was able to reproduce the issue with the default theme

Could the issue be due to extensions?

• I've ruled out the possibility that the extension is causing the problem.

Describe the problem

页面中的mermaid等渲染块在导出页面（如PDF导出、导出预览模式）无法显示完全，似乎与块的overflow、min-height样式有关

Expected result

正确显示渲染块

Screenshot or screen recording presentation

PDF导出：

导出预览：

Version environment

- Version: 2.12.2
- Operating System: macOS, Windows
- Browser (if used):

Log file

无

More information

No response