Thanks for working on a successor for CAD. It is still work in progress. I tested it on Firefox for Android and for Windows: It does not purge the morgue subfolder in storage/default cache, and I need the Graylist feature from CAD and FMN.

I use the Auto Tab Discard add-on to reduce ram usage. Auto-Clear Site Data must not clear cookies when tabs are discarded! Therefore I must revert to CAD and wait for a fix.

It is 10 months after you wrote:
" I do plan to open-source the project in the near future. However, making the code public carries a high risk of accidental sensitive data exposure. Therefore, I need to ensure I have a robust process to effectively sanitize and secure the code base before releasing it."
Everybody can open the xpi-file and see the code. There is no way and no need to hide anything.

Please, provide a home page beside AMO, at least add a bug tracker and discussions e.g. at Github. AMO is for reviews and not a place to track bugs and requests and to discuss issues.

It's still buggy. I've fully exempted Gemini but it logs me out everytime I restart the browser. More annoying is Amazon. It logs me out of Amazon when I'm browsing even when I have plenty of Amazon tabs open in my browser. I clicked the option "Pause Clearing This Domain" for 30 min. but it didn't do anything. I didn't want to exempt Amazon so I disabled this extension in order to finish my shopping.

I'm sure there's many other sites with issues. I hope the dev keeps improving this addon.

edit: it does this on mozilla.org also. This addon shouldn't log you out during the same browsing session while you still have those tabs open just because you're viewing a different tab.

The custom time option for Pause Clearing This Domain doesn't remember the number you set. It always goes back to 30 min.

A good replacement for a now-defunct extension, as many have pointed out; more specifically it seems to have much more robust options, aside from the lack of greylist vs whitelist. However, it seems to have an issue with Google sites in particular where it keeps randomly signing me out. I have added a number of other google subdomains to the whitelist, yet nothing seems to help. Other sites I use work fine however.