Allow scrolling when dragging links

[thibaultmol]

If you have a lot of links and you have to drag a link from all the way at the bottom to somewhere at the top or the reverse;
it's annoying that you can't just:

• grab the link
• use scroll wheel to get where you need to be
• let go

Scrolling doesn't work when you have grabbed a link, I presume because there might have been a bug there. But still submitting this because it would be nice to have