od Realraven (Axel Grude) (Vývojář) v Říj. 7, 2025 · trvalý odkaz

There is no filters API, so the Add-on needs to use the "experimental" model - which allows full access to the front end code, like all Add-ons until version 68 had. This also means that the complete source code is always reviewed by a security person before it is allowed to be listed on ATN. With this, the Add-on has the same system access as Thunderbird front-end code.

On the other hand, the permissions based Add-ons (web extensions / "mail extensions") that you prefer, can do what they want, but the user gives them permissions to certain parts, such as reading / writing emails, address book etc - and then it can pretty much do what it wants in those specific areas - for instance, harvest your data.

But like I said there is no web extensions API for doing anything with filters, so there are no native mail extensions that can do anything like adding custom filter conditions or actions. It's impossible for a standard mail extension at the moment. I am working with Thunderbird Core developers to get something like this off the ground but it is highly complicated and not prioritized,