However, in practice, I've rapidly found that I genuinely don't mind the new layout, and actually prefer it. (And I tend to be have a bad attitude to change in general). The reasons are:
* It's way faster to switch rooms
* You can filter on People by hitting the People filter button rather than having a dedicated section.
* I spent my life scrolling around the previous sections, or manually resizing them, etc, whereas the simplicity actually feels a bit refreshing and lighter weight.
That said, this is an initial release of the new room list, and there's a bunch of work to be done still:
* Need to support collapsing the LeftPanel like we used to be able to.
* There's a plan to re-introduce Sections again (so you can see your favourites etc separately to the main contents if you want - and reclaim muscle memory)
In terms of where to manage Sessions in Element Web/Desktop - it should always be the 'Sessions' tab in Settings? If your server is using native OIDC (i.e. matrix-authentication-service) then some of the management gets delegated to MAS and links through to account.matrix.org (or wherever your MAS lives). But if you can't see any way to manage Sessions, then it's likely a misconfiguration or a bug; please let us know the details.