Note that Firefox did show the line (and column, which is impossible to get in Chrome) number if you actually clicked on any point in the view-source window. It just didn't have a gutter on the left with the line numbers.
As far as the ruby tag, if you really are interested I'd be very glad to get you up to speed. There's a partial patch, but it has some issues that should really get dealt with before it lands. Of course every single ruby implementation out there is broken as hell in the relevant ways, so maybe it should just land issues and all... In any case, let me know if you do want to get it into shape. I do have to warn that this is not a small-and-simple project unless you really want to learn about the layout engine internals anyway.
Thanks for the offer. I would take you up on it but as you say (and I sort of expected) it's not going to be a simple project and I have a lot on my plate right now.
As far as the ruby tag, if you really are interested I'd be very glad to get you up to speed. There's a partial patch, but it has some issues that should really get dealt with before it lands. Of course every single ruby implementation out there is broken as hell in the relevant ways, so maybe it should just land issues and all... In any case, let me know if you do want to get it into shape. I do have to warn that this is not a small-and-simple project unless you really want to learn about the layout engine internals anyway.