Header (navbar) is not locked and scrolls away when you scroll down the page.

[BSTADIG]

Sometime between 0.14.4 and 0.15.1 the navbar started scrolling away, and leaving some unwanted effects on my site.
Is this intentional? How can I alter the CSS or templates to keep the header persistent?
/Björn

[drammock]

Reported in #1627 and fixed in #1630. You can install from current main if you need the fix right away.