It would be great if you could import open tabs.

What I really want/need is a tool that helps auto-categorize/group all my open tabs into areas of interest and enables full-text search across all of those pages so that I can context switch back into whatever I was working on at that time.

Manually bookmarking and tagging doesn't scale for me.

I don't think a web app can do this, but a browser extension, which is on our roadmap could!

Regarding auto-categorize, how would you want that to work? I imagine this could be a machine learning problem, but I wonder if there is a naive solution that solves most of the problem instead of just throwing ML at it?

Text search across pages has come up multiple times in this thread. I shall add it to our list of features to investigate.

I'm envisioning a number of categories that I can predefine or select as seed. I think Flipboard use to ask for a number of interest areas upon first use. Something like that.

I'm not always in favor of ML but I'd think this would be something ML would excel in.