Now this is an interesting use case. I am going to have to test a bit and circle back.

🎶..🎶 Please Hold, Pete 🎶...🎶

So, I have not found a way to run a bulk import yet and I do not think we'll find one out-of-the-box.

Navigate to the following setting (which it sounds like you likely have found already):

Open Thunderbird → Settings → Privacy & Security.

Scroll down to the Mail Content section.

You’ll see: Block remote content in messages (checkbox). & A button labeled Exceptions…., which you will now click.

There, you can add either specific email addresses or domains to either a block or whitelist. Thunderbird supports domain-level blocking and adding, but not the use of wildcard (*) characters, like you might see in outlook or gmail. (i.e. type @apple.com , not *@apple.com). That might be why you were not having luck with domain blocking when you tried.

What I would do: Export your data to CSV. Clean it so only actual email addresses and domains remain. Then add them one at a time or make a script to add them for you.

Too bad there is not an add-on for this.

I hope I helped you

yeah i know how to do it manually, but this list has grown over 10 years or so and doing it manually is just not feasible at this point.

If the team cares anything about people coming from outlook to TB I hope they pick it up. importing a flat file with emails/domains shouldnt be that difficult or require any additional hoops...

and no, "just create a script" is not something i could do...

thanks anyway for taking the time and looking into this, Pete

Hey Pete, I hear you. A 10-year list isn’t something anyone should be clicking through by hand. We do care about folks coming from Outlook to Thunderbird, a lot. I’ve spent the last three hours (it’s 3:40 am here btw 🙃) building a small add-on from scratch to do exactly what you asked for. I hope you feel heard.

I even named it “Trusty Pete” in your honor, and it’s meant to have your back. 🐦

It imports a flat file (TXT or CSV, one address or domain per line) into Thunderbird without scripts or extra hoops. It’s an early prototype, but it works on my side. It is 'experimental', and it will ask the user for a couple of additional permissions that we do not normally surface in standard add ons. These permissions are only used to import and manage the list.

If you’re up for it, Feel free to DM me a small sample list (redacted is fine) so I can double check that it handles your format. If it does the trick, I’ll polish it and share an installable build via the Add-on market.

Thanks for pushing on this. Feedback like yours helps us focus on the right things. 🙏

amazing! I might migrate to TB after all! I will follow up with an excerp in a DM.

OK Pete. It's built. It's an add-on and I have submitted it for review by our add-on team. If [once] approved, it will be available for download to millions of users. I'll let you know.