Sidebar width setting: apply globally or per window

[tzinm]

Currently, when adjusting the sidebar width using the keyboard shortcut, the change applies to all open Zen Browser windows.

It would be useful to have a setting (checkbox) that allows users to choose whether the change should apply only to the current window or globally across all windows.

Motivation

Sometimes, I work with two browser windows side by side, each occupying a different percentage of the screen.

For example, if one window takes up 75% of the space and the other 25%, it would be great to keep the normal sidebar width in the first window and the compact mode in the second.

This option would enhance flexibility and improve the user experience by allowing interface customization based on the usage context of each window.

[arborealoctopus]

+1

I thought this was resolved with this issue: #4165
but apparently collapsing the sidebar and compact mode are different in ways I don't understand. I believe the same justification applies in both cases, and my use case is identical to tzinm's.

I'd also add that my "perfect" version of this feature is that you can select a default and new windows will always do that default. With the compact mode toggle above, the immediate problem that makes the feature annoying to use is that its "sticky" to whatever you set in the most recent window. I don't understand the use case for such a behavior (not that its uncommon in the world of software, including things like window sizing and placement -- its just...not pleasant for users).

[JosefSaltz]

Also looking for this feature as a triple monitor portrait-ultrawide-portrait user. The per window compact mode resolved in #415 is definitely helpful but also being able to set my my sidebar width per window would really complete the customization experience.