Google Workspace is rolling out a reply button in Spaces within Google Chat, we LOVE this. It's now quick and easy to reply to a message and use threads.
Step 1 - You will notice the reply button under a message sent in the Space.
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Step 2 - Click reply and this will open the thread to compose your response. Use the follow button to receive notifications for replies.
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Step 3 - You will notice it now says 1 reply, you can click this to open the thread.
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This is the best way to use Spaces for productive and organised communication.