I'm not sure if this is the best place to report this but at some point after 2020Q4 the package znapzend stops working because of the following:
Can't locate object method "delay" via package "Mojo::IOLoop" at /opt/tools/lib/perl5/vendor_perl/5.36.0/Mojo/IOLoop/ForkCall.pm line 27.
A quick web search reveals that "delay" has been deprecated in that perl module.
I believe this dependency has been fixed in newer versions of znapzend.