This thread is resolved. Here is a description of the problem and solution.
Problem:
You encountered a critical error when trying to access the 'Theme and plugins localization' feature in WPML. The error message indicated an 'Unknown format specifier 't'' in a specific file related to WPML String Translation.
Solution:
We recommend checking if this issue is related to a known problem with plugins registering a text domain incorrectly. You can find a workaround for a similar issue on our errata page: https://wpml.org/errata/flux-checkout-fatal-error-uncaught-valueerror-unknown-format-specifier-t/.
If this solution does not apply to your case, or if it seems outdated, we highly recommend opening a new support ticket. Additionally, please check related known issues at https://wpml.org/known-issues/, verify the version of the permanent fix, and confirm that you have installed the latest versions of themes and plugins. For further assistance, you can also visit our support forum at https://wpml.org/forums/forum/english-support/.
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