Dear @Czarnecki, Lukasz,
Thank you for reaching out to Microsoft Q&A forum. We are happy to assist.
Since you’ve written this thread in English, I’ll reply in English as well. If anything is unclear or misunderstood, please feel free to let me know.
This issue is quite advanced and closely related to the XML structure you are using. Since custom text fields are highly specialized, I recommend posting your question on the https://techcommunity.microsoft.com/ where experts in coding and development can provide the best approach.
When you post, include your XML file if necessary, but make sure to mask any personal or sensitive information.
In addition, I found two articles about XML and custom fields that you may find helpful. Kindly review them for more insights:
Custom Field Data in XML
XML Schema for the ExtendedAttributes Element
I truly appreciate your understanding and patience. If you have any other questions, don’t hesitate to reach out. I’m happy to help.
If you found the answer useful, please click "Accepted Answer" and kindly give it an upvote.
If you have any follow-up questions, feel free to click "Comment" to continue the discussion.
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