Discussion index page

Description

Sometimes I want to look up the past discussions already resolved in an MR. Like, the 2nd reviewer points out a code already discussed&resolved with the 1st reviewer, and I just want to paste the past discussion(a comment) link to there. However, currently it's hard to do because all resolved discussions are collapsed, and there no buttons to open all of them, at least you need to click one by one now. Then I just thought it's good to have a discussion index page instead of creating a new button in MR page.

Proposal