https://webartdevelopers.com/blog/scroll-progress-bar/
SCROLL PROGRESS BAR
scroll progress bar
https://myext.info/extension/Scroll-Progress-Bar/dfejgdncgcidoeabmpdfbibmmkfbbbaf.html
Scroll Progress Bar :: My Extensions
Scroll Progress Bar Simple and unobtrusive horizontal progress bar to show how far down a webpage you have scrolled.
scroll progress barextensions