Hi Chris,
Yeah, they made it difficult to grab addresses from the message - you can do it from the message source.
Click on the dots to the right of Reply/Forward and choose View Message Source - click in the source and the Ctrl+F to find - type subject and click through till the message subject comes up. (Searching for From works too)
It will look like this;
From: Diane Poremsky <my address>
To: Contrary <my outlook.com address>, Diane Poremsky <my other address>,
Diane Poremsky <yes, i have too many addresses :) >
Subject: Test
copy the addresses and paste wherever.