Features

Copy the build ID or list of extensions to the clipboard using the toolbar button
Insert the build ID or list of extensions into a textbox using the context menu
Option to customize the Title Bar
Available locales: Chinese (Simplified), Czech, English, Japanese, Polish, Russian, Swedish

Limitations There are a couple of known issues due to the limited WebExtensions APIs:

The changeset cannot be retrieved
The extension list does not include system add-ons
The textbox inserting options don't work on some Mozilla sites (including AMO due to a security restriction) as well as with a textbox within an iframe and certain rich text editors
Some variables are not available for the custom title template

The following features found in the original XUL-based extension are not yet implemented, and some of them may not be implemented again: