Add-agent-buttons adds third element when rendering the view for apps (only in tests)

When working on https://github.com/solid/solid-ui/pull/232 I had to fix a test that broke. It's the test When "Add App" button is clicked > bar is simplified that is affected. It expects two elements to remain after Add App button is clicked, but for some reason three elements remain after the action.

This only happens in the test, I have not been able to reproduce it "manually".

I've tried to understand why this happens, but have succumbed to let it be for now, as there are more urgent matters to tend to. But creating this issue to track it, to revisit it when I have time, or if others are more lucky than me.

Issue で言及されている When "Add App" button is clicked > bar is simplified テストから始めて、失敗を再現してください。Add App アクションによって実行される rendering を追跡し、テストで 3 つの要素が残る理由を特定してください。完了の条件は、関連する動作を壊すことなく、テストが常に残り 2 つの要素を確認できることです。