This update for claws-mail fixes the following issues:
Update to 3.17.6:
It is now possible to 'Inherit Folder properties and processing
rules from parent folder' when creating new folders with the
move message and copy message dialogues.
A Phishing warning is now shown when copying a phishing URL, (in
addition to clicking a phishing URL).
The progress window when importing an mbox file is now more
responsive.
A warning dialogue is shown if the selected privacy system is
'None' and automatic signing amd/or encrypting is enabled.
Python plugin: pkgconfig is now used to check for python2. This
enables the Python plugin (which uses python2) to be built on
newer systems which have both python2 and python3.
CVE-2020-15917: Fixed an improper handling of suffix data after STARTTLS is mishandled (boo#1174457).