Sub-directory URL and Gravity Form File Upload

This client’s site is in French, and the secondary language is English. It uses sub-directory URL structure so the English routes would be prefixed with /en/.

The issue is with Gravity Forms with file uploads. The form in French works fine, but the translated form in English won’t upload at all. I went into the back end and logged form requests, and in both languages the $_POST array works as intended, but the $_FILES array would be empty only for the English form.

I tested with the sub-directory URL structure disabled, and in both languages the $_FILES array works fine. There are no unintended redirect rules defined in the .htaccess file. So it seems the sub-directory URL structure doesn’t work with file uploads in different languages?

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