Steps to reproduce

1. Install Ibexa DXP v3.3.
2. Create a new language, for example French.
3. Install the ezplatform-i18n-fr_fr package.
4. Create a custom attribute with rich text for the Form builder.
5. Change the language for the Back Office to French.
6. Create a form and use the created custom attribute.
7. Check the titles of alignment or dropdown of headers.

Result

Expected

All translations should be loaded correctly, for regular richtext, e.g. in an article, everything works fine