More visible cursors

[adzialocha]

It could be nice to make the visible cursors of other authors slightly larger (2-3px?) to get a better idea of their color and also it's maybe nice to highlight the "collaborative" nature?

[bertob]

I agree that cursors could be more visible, but I think the biggest problem is the color, rather than the width. Some of the lighter colors are incredibly hard to see on a light background, and vice versa for dark. I'd start by adding two colors for each avatar color: A darker color for the cursor in light mode, and a lighter one for the cursor in dark mode. If that's not enough we can still try increasing the width, but without that I don't think it would help.

Is there a list of all the avatar colors somewhere? I can prepare dark/light cursor variants for each.