Captcha generation fails with libpng1.6 (≥ 1.6.32)
Since version 1.6.32 of libpng1.6, Captcha generation may fail randomly and a "chunk data is too large" error is reported. This is a Authen::Captcha error reported to [rt.cpan.org|https://rt.cpan.org/Ticket/Display.html?id=123029].
Note that LLNG ≥ 2.0.0 is not affected by this bug
Solution:
- Debian users: use libauthen-captcha-perl ≥ 1.024-2
- Other distribution: replace {{perl-path/Authen/Captcha/images/background5.png}} by the one proposed below