Greasy Fork is available in English.
Support for over 70 sites! Loads manga chapter into one page in a long strip format, supports switching chapters, minimal script with no dependencies, easy to implement new sites, loads quickly and works on mobile devices through bookmarklet
< Feedback on Manga Loader (unmaintained)
Added to 1.9.35 about a month ago.
Site Request: MangaEden
I don't know if it has been suggested before. But please add MangaEden. Here's the homepage: http://www.mangaeden.com/