Oh, I see. My mistake, Gmail doesn’t apparently have a concept of an “archive folder”.
From Archiving Messages
With Gmail, “archiving” is a built-in concept and removes the Inbox label from the conversation. After archiving, you can view the conversation by going to “All Mail” in the sidebar (which Mailspring may show as “Archive” if you have multiple accounts linked), or by viewing a label that was applied to the conversation.
Does that clarify anything, @greenisagoodcolor, or are you still stuck?
P.S. I’m just the community manager, not the primary developer, so I don’t always know all the ins and outs.