Mousewheel scrolling is a decent way of navigating a web page. If you know what you're looking for, a text search is faster. But what if you're not quite sure where the information you need is? If you're using Firefox, then Mathieu Pillard's Minimap Scroller might help.
First, you should be aware that the addon, which can be found on Mozilla's official addon site, is experimental.
As the creator notes on the GitHub repo, a lot of work is still required on the performance and memory consumption fronts.
Still, even in its beta state, the addon runs as expected. Once installed, you'll need to turn it on via the sidebar button. After that, when you visit a page, it'll load a horizontal overview that'll track your position on the page, or you can click it directly to navigate immediately.
The size of the minimap can be scaled by increasing or decreasing the width of the sidebar.
Depending on your computer's specifications, it might be too demanding to use all the time, so don't feel bad if you need to bookmark it for now until the developer is able to beat it into shape.