The user-friendly, lightweight, and fast email client Latest Release: 3.19.0 / 4.1.0 (News), on 3 April 2022

The Bogofilter plugin

The Bogofilter plugin provides anti-spam capabilities for Claws Mail. Bogofilter is a pure Bayesian filter, written in C, which makes it very fast. Claws Mail also provides a SpamAssassin anti-spam plugin, with the same feature set, but more extensive 'spaminess' checks. The Bogofilter plugin features are: Before Bogofilter is able to function effectively, you have to show it a few of your spam emails and a few real emails. You can do that by selecting some messages, right-clicking on them and choosing 'Mark/Mark as spam' or 'Mark/Mark as ham'.

Bogofilter is required, https://www.bogofilter.org/

Here are a few screenshots illustrating the features: