I have a layout where the session conversation is in the left, in the right I...

This is for Github Copilot App: I have a layout where the session conversation is in the left, in the right I have two panels one in the top right and one below it, in the oper one I have the changes, plan and Files, in the lower one I have terminals. The problem happened wihen trying to open a Files tab in the lower panel by clicking the plus (+) in that panel, the Files tab was opened in the top panel.

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| Field | Value |
| --- | --- |
| App version | 1.0.23 |
| OS | macOS 26.5.2 |
| Theme | Xotopio |
| Path | /chat |
| Tenure | Week 5 |

使用所描述的双面板布局，在 /chat 的 GitHub Copilot 应用中重现该问题，然后检查下方面板如何通过其加号按钮打开标签页。完成的标准是：在下方面板中选择 Files 时，它会在下方面板中打开，而不是在上方面板中打开。

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