But they have identical sources listed and `apt` produces warnings on an update. Is it safe to delete one of it? If so, which one?
# cat plesk-ext-site-import.list
deb [arch=amd64] http://autoinstall.plesk.com/PMM_0.1.11 xenial all
# cat plesk-ext-panel-migrator.list
deb [arch=amd64]...