Side Scrollbar disappears frequently in the New Teams.

I believe this is part of the most recent Teams update. over 300 users at my company have experienced this after the update. This is not a 1 off issue.

So its either a bug they need to fix or a change Microsoft made to try and make Teams looks more seamless but with the loss of a function that a lot of users like. The only way for the bar to show back up temporarily is to scroll with a mouse or scroll with the touch pad.

Facing exactly the same issue with the new Teams. Exactly as in the screenshot. Minimizing the recent chats brings back the whole list of the pinned chats but this is not a long term solution.
This is clearly a bug in the new Microsoft Teams.

I'm having the same issue, I've found the only way for the scroll bar to come back is to minimise the Teams window, it's not a long term solution, hopefully Microsoft will acknowledge this issue and update the app soon.

It's working fine if I login to https://teams.microsoft.com and I'm facing the problem only in the New Teams App, The earlier version of the Teams app appears to be fine.

If you look at the below screenshot, I'm in the Chat option and the scrollbar is not visible in the chat window.