text: Title: No scrollbar (overflow: hidden) in dev documentation when using Fast template
  Body: When opening the `dev` docs on a page that uses the Fast template there is no scrollbar. For example https://holoviz-dev.github.io/panel/tutorials/basic/build_crossfilter_dashboard.html
  
  I believe it won't make sense to release Panel 1.4.5 or 1.5.0 before this is fixed @philippjfr .
  
  ![image](https://github.com/user-attachments/assets/852c971e-3267-4a5f-b41a-5c70de65ca29)
  