Designed for reading long articles or highlighting a specific passage. Click it and it'll make a bookmark that saves where you were! If someone else has the extension, just share the bookmark with them, it'll work.
Works by saving your scroll position in the fragment identifier (hashcode) of the bookmark URL and scrolling to it. The code's open source, see it here.
Developer comments
Doesn't work on system pages (e.g PDF pages) due to a bug in Firefox. Report bugs at the issues tab at the Github repository.
Report bugs at the issues tab at the Github repository.