Hi @Marc D7
Thank you for your post!
I understand that you're facing an issue with localization for AD B2C User Flow Sign-In page when you switch the language.
To resolve your issue, you need Enable and Customize your strings in your user flow for that you need to Download the default Page-level resource files and overrides the strigs in defaults with your own content this way you can achieve your ask.
In your case download the Unified sign up or sign in page defaults
Step: -1
Step-2
Open the default Page-level resource files and overrides the strigs by changing false to true, if you would like to change the complete page change all the elements override to true
Save the file and upload to the Page-level resource files and run the user flow.
Hope this helps. Do let us know if you any further queries.
Thanks,
Akhilesh.
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