column headers obscure unread information after page down

I'm using phanpy with the multiple columns feature enabled. At the top of the column there is a header. Sometimes, a post will be partially visible at the bottom of the screen. I press page down to view the rest. But that moves the rest of the post to be underneath the header, so I cannot read it.

See attached screenshot demonstrating the problem. I highlighted the affected post with a red outline.

**Desktop (please complete the following information):**
- OS: linux
- Browser firefox
- Version 120

Reproduce the issue in Firefox with Phanpy's multiple-columns feature enabled: leave a post partially visible, then press Page Down and confirm that the column header covers the remaining content. Done means the post remains fully readable after Page Down while the header stays in place.

Written by the indexing model from the issue text.