NOTE: All tests are to be performed on PHP 7. There are virtual machines with PHP 7 if you don't have it.
# change any SQL that will be executed
# open the page, where SQL should be executed
# open debugger
# confirm, that SQL is properly reported as containing error
# open any list of items (e.g. in Admin Console)
# confirm, that debugger doesn't container any notices about `$Array` usage
# open list of links in a category on the Front-End
# confirm, that debugger doesn't container any notices about `$Array` usage
# create new form in {nav Website & Content > Forms} section
# for that form enable e-mail communication on tab with same name (fields in `Bounce` sub-section aren't required)
# for that form create `Name` and `Email` fields, which needs to be mapped to `Name` and `Email` roles in e-mail communication
# send an e-mail to e-mail address specified during form configuration
# run `tools/cron.php` script from CLI to check that e-mail for new messages
# confirm, that new form submission have appeared in {nav Website & Content > Forms > Your Form Name} section