This is a huge problem. I have seen HubSpot reps recommend that we forward emails to managers for approval, but forwarding HTML email often injects issues with formatting and is not a workable solution. Please reinstate publicly shareable preview links that do not require a HubSpot login, as this is really the only way to solve this problem. Mailchimp is significantly less powerful than HubSpot, but they have publicly shareable preview links easily accessible in their system. Many other mass email systems do as well. HubSpot is typically the leader in finding ways to surprise and delight its users, and I’m sure that you can find a way to do it in this area as well.