The Code is the Design

From terminal: cat Duplicates.txt | sort | uniq -c > Counts.txt Within vi: :%sort         // sort the results as required by "uniq" :%!uniq -c   // use the *nix "uniq" tool to prepend counts :%sort!        // sort in reverse order

Linux sendmail sometimes drops emails mysteriously without any error message or log of the written email. /var/log/maillog will show an entries such as: Unauthenticated email from xyz.com is not accepted due to [DMARC] The way to fix this is to have the domain name of the current server in the from field, and the actual from address in the reply-to field. This can easily be done with Drupal 7 using the contact_reply_to module. Drupal 8 does not require the module.

Module pages usually say: "The most complete and up to date documentation is included with the module, in the README.txt file." But the online README.txt files linked to there usually include documentation for unreleased updates. This can cause considerable confusion / unnecessary trouble-shooting when newly installing modules. Always use the README files included with the module, not the ones online.