Rated 5 out of 5 stars

The idea behind this add-on is good and it should get in the focus again: With abused IoT devices sending spam nowadays hashcash is an effective measure (amongst others) for spam detection.

The plugin works in recent TB 52.4.0. When setting up, don't forget to place the icon for stamping messages onto your message composition window.

Rated 5 out of 5 stars

As said before: A good accessory in the war against spam.
Works flawless here.
I would like to see more people use it.

Working on a version with support for verifying stamps in native javascript so no extra settings is needed after installing. Maybe that will bring more users :-)

Rated 5 out of 5 stars

Good technology experiment to slowsdown spammers with sending spam. Using the generated e-mail header with your outgoing mail makes it possible to improve your delivery chance to the inbox instead of the spam folder.
This addon depends on Java(JRE) and that has to be installed and configured to be able to use this extension. This is sadly not easy to use for most average computer users.

This review is for a previous version of the add-on (1.5.3). 

Rated 5 out of 5 stars

Don't know why my earlier review got deleted. Like the post title says, works perfectly. Don't forget to follow the configuration instructions. Recommend setting HashCash token to 22 bits: full point reduction in spamassassin for only a few seconds of minting time.

This review is for a previous version of the add-on (1.5.3). 

Hope this post from me, the maintainer of the code will keep your review up.