I can't find it maybe you can help me!
The tool I use now for collaboration on design work is InVision. I really like it only it doesn't work great with large projects (more than 100 screens). But that aside I want to get the same collaboration only on a static website.
I found this together.js from Mozilla Labs: https://togetherjs.com/ This would be perfect but I miss is the function to give comments and react on those.
I found Red Pen as well: https://redpen.io/ But I'm not sure if you can implement this on your own website. Probably not, they use an app as well.
Do any of you have used together.js or found something to do this?