Closing a Split Tab in one Zen window causes other windows' tabs to change to the remaining tab

Preliminary Checks

• I have read and understood the important section above.
• I have searched existing issues and avoided creating duplicates.
• I am not filing an enhancement request.
• I have checked that this issue cannot be reproduced on Mozilla Firefox.
• I have checked that this issue can be reproduced once I removed all my Mods and Custom CSS.

What happened?

When multiple Zen windows are open, closing a split tab in one window will cause the other windows displaying the same space to flash and open (or attempt to open) the remaining tab from the split. Ideally, closing the tab would only affect the window you are on (and the sidebars of the other windows), without changing the focus of the other windows to the remaining tab.

Expected behavior

When closing a split tab in one window, I would expect it to close the tab in that window, filling that window with the remaining tab, while not affect what any other window is displaying.

Actual behavior

Closing a tab from the split is causing all other open windows within the same space to load the remaining tab simultaneously as their active tabs.

Steps to reproduce

1. Open two separate Zen windows using the same space
2. In one window, load any website
3. In the other window, load any two websites, and add them to a split
4. Close one website from the split; both windows will update to view the remaining tab

Screenshots and videos

https://github.com/user-attachments/assets/a65aa575-92d6-41ad-bb8e-d70ed1da850e

Version

1.19.13b (Firefox 150.0.3) (64-bit)

What platform are you seeing the problem on?

Windows - x64

What component is this issue related to?

Split View

Relevant log output if applicable