Is this project still active ?

[iTrooz]

I see a lot of issues and activity, but the last commit is dated from 2019

What is going on ?

[ghost]

This program is no longer being developed. It has been abandoned. I recommend that you discontinue use of this program for vulnerability protection purposes.

[iTrooz]

Do you have an alternative in mind ?

In particular, I love the feature to delete every cookie on close, except some

I use that to whitelist the websites I want to stay logged in, and only in particular profiles

[ghost]

It can be done with the standard features of Firefox.
Select Manage Exceptions from Privacy and Security in Settings.

[iTrooz]

Can it save cookies only in certain profiles ? I thought the whitelist was profile-wide, which isn't that bad, but I prefer the current way of only saving cookies for site X for profile Y