See https://bugs.koha-community.org/bugzilla3/attachment.cgi?id=155782 Back from holiday, might be a bit rusty, but this is a weird behaviour. If you send test => [] from pl, [% test %] will display an empty string, and [% test.size %] won't display 0 We may need to check some occurrences of % git grep '\.size == 0' **/*.tt **/*.inc