Hi Tina
Apologies, my screenshot probably could have been clearer.
My screenshot comes from editing the Timeline component from within an existing form that has it attached. When you select it, certainly in the modern interface (make.powerapps.com) you will get a sidebar as below:
Clicking one of the Activity Types then provides the 'dialogue' displayed in my last post, you can also drag the different quick actions to set some sort of order. It is worth noting that you can configure Timelines on different entities entirely independently, so can have different behaviour on each.
Hope this helps
Regards
Matt
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Matthew Vizor
Shelter
London
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Original Message:
Sent: Oct 06, 2022 12:39 PM
From: Tina Silver
Subject: Wave 2 2022 I can no longer reply to an email in the timeline and have the email record open automatically
Thanks, Matt. Can you tell me which Table (entity) you went into to grab this screenshot? I have been into both Cases and Email, and I don't see "E-Mail" like you do at the top of your screenshot, I just see Email. I want to check out where you are looking as well. 
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Tina Silver
Sr BSA, CSM®
SR Smith, LLC
Canby OR
Original Message:
Sent: Oct 06, 2022 03:50 AM
From: Matthew Vizor
Subject: Wave 2 2022 I can no longer reply to an email in the timeline and have the email record open automatically
Hi Tina
have you checked the configuration of emails on the Timeline?
I haven't tried it, but seem to remember reading that the above configures the 'quick actions' on an Activity entity
Apologies if I'm wrong, but always worth checking
Kind regards
Matt
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Matthew Vizor
Shelter
London
Original Message:
Sent: Oct 05, 2022 09:51 PM
From: Tina Silver
Subject: Wave 2 2022 I can no longer reply to an email in the timeline and have the email record open automatically
Today while testing Wave 2 2022 in my sandbox environment, I was no longer able to reply to an email in the Timeline and have it automatically open the Email record. (I do not have this issue in my Dev environment (where we first installed the Wave.) I have to refresh the Case, then the email is at the top of the Timeline. I can open the Email record, enter my response and send it with no issues. I also noticed that when I Reply or Reply to All, the To value no longer defaults onto the email. I'm wondering if anyone else is noticing odd behavior since Monday.
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Tina Silver
Sr BSA, CSM®
SR Smith, LLC
Canby OR
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