I'll set the scene that I think most of us have experienced: you're working on a project. You start down the rabbit hole of research to find a solution to something. Maybe you find it quickly somehow. But this case, you don't. The problem is too big for an easy answer and instead requires synthesis and reflection.
Eventually, after opening 50 tabs and only closing the immediately useless stuff, you find that you need to circle back up the problem solving chain. The problem is that you have 45 tabs open and no method to the madness that is clearly visible.
This further compounds if you're trying to solve a new problem with an existing set of tabs that haven't been cleaned out from the last problem.
Nowhere in this process is the UX leading you to solving a problem.
My half-baked solution is to allow for the user to enter "research mode". When a new tab is opened, the browser halts the user and prompts for what they found on the last tab that led them to opening this new tab. When the user leaves research mode, any leafs left should also prompt for a summary or omitted as irrelevant. Then, once all the tabs have been accounted for, a report can be generated which shows all the URLs and the user's notes. Bonus points if allows generation of MLA / APA citations automagically. Further bonus points if I can highlight sections of text / images while in research mode to fill my new tab questionnaire as I go.