Jetpack Backup: WordPress 6.8 compatibility - _load_textdomain_just_in_time doing it wrong notice being logged

[coder-karen]

Issue

In testing with WordPress 6.8-beta2, I noticed a _load_textdomain_just_in_time 'doing it wrong' notice being logged for Jetpack Backup (and the notice doesn't appear to be visible in 6.7.0 or 6.7.1/6.7.2 despite the message, for US English (visible for other translations though) ):

PHP Notice:  Function _load_textdomain_just_in_time was called <strong>incorrectly</strong>. Translation loading for the <code>jetpack-backup</code> domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the <code>init</code> action or later. Please see <a href="https://developer.wordpress.org/advanced-administration/debug/debug-wordpress/">Debugging in WordPress</a> for more information. (This message was added in version 6.7.0.) in /var/www/html/wp-includes/functions.php on line 6121

The following stack trace is logged by adding extra debugging in the l10n.php file:

Stack trace:
#0 /var/www/html/wp-includes/l10n.php(1412): _load_textdomain_just_in_time()
#1 /var/www/html/wp-includes/l10n.php(195): get_translations_for_domain()
#2 /var/www/html/wp-includes/l10n.php(307): translate()
#3 /usr/local/src/jetpack-monorepo/projects/packages/assets/src/class-assets.php(664): __()
#4 /var/www/html/wp-includes/class-wp-hook.php(324): Automattic\Jetpack\Assets::filter_gettext()
#5 /var/www/html/wp-includes/plugin.php(205): WP_Hook->apply_filters()
#6 /var/www/html/wp-includes/l10n.php(220): apply_filters()
#7 /var/www/html/wp-includes/l10n.php(307): translate()
#8 /usr/local/src/jetpack-monorepo/projects/packages/backup/src/class-jetpack-backup.php(123): __()
#9 /usr/local/src/jetpack-monorepo/projects/plugins/backup/jetpack-backup.php(185): Automattic\Jetpack\Backup\V0005\Jetpack_Backup::initialize()
#10 /var/www/html/wp-settings.php(545): include_once('...')
#11 /var/www/html/wp-config.php(119): require_once('...')
#12 /var/www/html/wp-load.php(50): require_once('...')
#13 /var/www/html/wp-admin/admin.php(35): require_once('...')
#14 {main}

Steps to replicate

On a self-hosted test site, with Jetpack Backup installed and active:

• Install the WordPress Beta Tester plugin
• Go to Tools > Beta Testing, and set the plugin to use Beta/RC Only (in order to upgrade to WP 6.8-beta2)
• Go to Dashboard > Updates, and update to WP 6.8-beta2.
• Load any page, and check error logs. You should see PHP Notice: Function _load_textdomain_just_in_time was called <strong>incorrectly</strong>. Translation loading for the <code>jetpack-backup</code> domain was triggered too early.

Also replicable in WP 6.7.2 with a translation such as Deutsch, if WordPress is reinstalled using the new language.

Other relevant links

WordPress 6.8 compatibility parent issue: #39818

[github-actions]

OpenAI suggested the following labels for this issue:

• [Feature Group] Content Management: The issue involves compatibility and potentially incorrect loading of translations related to the Jetpack Backup plugin, which is part of content management.
• [Feature] Backup & Scan: The issue is specifically related to Jetpack Backup, so this label directly addresses the functionality impacted by the notice.
• [Feature] Error Reporting: The logging of a PHP notice indicates there’s a need for error reporting to help developers address the issue.