This thread is resolved. Here is a description of the problem and solution.
Problem:
You are using WPML and encountered an error: Uncaught Error: WPMLStringTranslationInfrastructureStringGettextRepositoryFrontendQueueJsonRepository::get(): Return value must be of type array, null returned.
Solution:
We are currently investigating a similar issue. In the meantime, we recommend following this workaround to help resolve the issue. Please ensure that you back up your database before making any changes. For detailed instructions, visit WPML Errata.
If this solution does not apply to your case, or if it seems outdated, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If you still need assistance, please open a new support ticket at WPML support forum.
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