wp-admin/includes/class-language-pack-upgrader.php:112Initializes the upgrade strings.
public function upgrade_strings() { $this->strings['starting_upgrade'] = __( 'Some of your translations need updating. Sit tight for a few more seconds while they are updated as well.' ); $this->strings['up_to_date'] = __( 'Your translations are all up to date.' ); $this->strings['no_package'] = __( 'Update package not available.' ); /* translators: %s: Package URL. */ $this->strings['downloading_package'] = sprintf( __( 'Downloading translation from %s…' ), '<span class="code pre">%s</span>' ); $this->strings['unpack_package'] = __( 'Unpacking the update…' ); $this->strings['process_failed'] = __( 'Translation update failed.' ); $this->strings['process_success'] = __( 'Translation updated successfully.' ); $this->strings['remove_old'] = __( 'Removing the old version of the translation…' ); $this->strings['remove_old_failed'] = __( 'Could not remove the old translation.' ); }Introduced in 3.7.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-admin/includes/class-language-pack-upgrader.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.