[Bug] When third window created, the leftmost menu in the bottom toolbar can not be clicked.

Hi!
I create 2 windows, on each window I can click the leftmost menu in the bottom toolbar, however, when I create another window, the leftmost menu in the bottom toolbar of the third window cannot be clicked, even after rebooting WindTerm.

Version: 2.6.0 Pre-release

Reproduce the issue in WindTerm 2.6.0 Pre-release by opening three windows and testing the leftmost menu in the bottom toolbar of the third window. Inspect the multi-window and bottom-toolbar handling; it is done when that menu can be clicked normally in the third window as well as the first two.

Written by the indexing model from the issue text.