Howto start developing TB addons (resources, etc.)?

Dear Community,
I would like to develop an addon for TB which will help me store my emails to either my sql database or one of my folders. It will do the following:

  • a new “Store/File” button
  • if I press the button it will show me a popup with different buttons
  • and i will copy the email content and attachments separately to the sql / folder.

I was looking for a tutorial, but whatever I found said it was obsolete, and the following doesn’t look like a howto: “Thunderbird 57-60 Add-ons Guide”

What would you recommend, where and how would you start?

Thank you!

I found this and hope it helps. I’m not a developer so can’t help to answer any questions you may have in the future.

Thunderbird WebExtension APIs

There’s this new overview, too: https://developer.thunderbird.net/add-ons/about-add-ons