If output window is not visible

Fixes #1767

I have:

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• Updated the [Unreleased] entry in CHANGELOG.md, linking the issue(s) that the PR is addressing.
• Figured if anything about the fix warrants tests on Mac/Linux/Windows/Remote/Whatever, and either tested it there if so, or mentioned it in the PR.
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  • Smoke tested the extension as such.
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Ping @PEZ, @bpringe, @corasaurus-hex, @Cyrik