Option to enable by default in private window

[Atemu]

Up until now, I had to resort to configuring Firefox to use DDG in private windows since Kagi is (in theory) linked to my account.

With this extension, that is of course a thing that can be remedied. (Really great job btw.; I was not expecting this.)
I have already installed the add-on into TOR-browser where I think it's most useful.

In my regular browser profile however, I'd like to continue to use Kagi regularly all of its ranking features, bells and whistles however; Kagi privacy pass isn't something I'd like to have turned on most of the time.

I do also use private windows from time to time where I expect to not be tracked; even by the software I trust (e.g. my browser history or my search engine). It'd be great if the extension could be configured to only enable privacy pass functionality in that context.
This setting should probably even be enabled by default as that would be the least surprising behaviour when installing an add-on specifically for privacy.

As for UX, it'd probably be best to simply have it be a separate toggle in the main view. There's more than enough space and this would make the configuration state immediately obvious to the user.