Change active tab background color when layout changes

[chriszarate]

This is something I've been trying to accomplish in a kitten but am really struggling to figure out. I would like to change the color (or append something to the title—really any kind of indicator) when the layout changes. This is something that comes out of the box in tmux (it appends *Z to zoomed panes) and is easily customizable with window_zoomed_flag. Is this possible in kitty?

I am using the zoom_toggle kitten provided in the docs and would like to extend that. Changing the active_tab_background color changes it for every tab, not just the one that has a different layout. Changing the title changes it permanently. I've been scouring the source code but can't find the right hook. Has anybody accomplished something similar?

[chriszarate]

Thanks!

[chriszarate]

Follow-up note for anyone searching for how to implement a tmux-style "zoom flag": This feature landed in 0.18. This is how I use it to show a count of "hidden" windows when the tab is zoomed:

tab_title_template " {title}{' +%s' % (num_windows - 1) if (layout_name == 'stack' and num_windows > 1) else ''} "

In a tab with 3 windows using the stack layout, this would result in this tab title:

~/Downloads +2