When terminal titlebar is turned off, there is no way to tell which window is currently active.
If a border would be drawn around terminal pane, then it would be much easier to distinguish which pane is currently active.
Here is an example:

How would you know which pane is currently active and if you would start typing, where your keystrokes would go?
You can use dimming to do this, it can be set in the profile color page if I recall correctly. No plans to offer something different.
Thanks, the property is called Unfocused dim and it is under color tab. It helps a bit, but still, not easy to identify active pane, especially when screen is mostly blank. And I can't dim too much, because I still want to clearly see inactive panes. I like how this is solved in kitty, with a border around active pane.
Thanks, anyway.
Here is how it looks with dimming:

Slightly better.
Sorry but that's all I've got, I don't have any plans to add support for outlining the current terminal.
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Thanks, the property is called Unfocused dim and it is under color tab. It helps a bit, but still, not easy to identify active pane, especially when screen is mostly blank. And I can't dim too much, because I still want to clearly see inactive panes. I like how this is solved in kitty, with a border around active pane.
Thanks, anyway.
Here is how it looks with dimming:
Slightly better.