Site can be scrolled further down, past the footer

**Describe the bug**
Sometimes (unclear when) the site can be scolled down past the footer. There is no content there, just a lonely scrollbar. It probably is an issue with how the sections are being rendered (via the main navigation in the header), where the site "forgets" that only some of the content is currently visible and lets you scroll all the way to the bottom of "where we could go if all content was displayed on one page".

**To Reproduce**
Steps to reproduce the behavior:
-

**Expected behavior**
Can't scroll beyond the footer in any section.

**Screenshots**
-

**Desktop (please complete the following information):**
- OS: Linux+Chrome, Windows+Edge

**Smartphone (please complete the following information):**
-

**Additional context**
-