Save data from to app from quicklook extensions

I have an iOS app with custom file formats and a quicklook extension. I want to be able to save the file into the app without the need to "share" the file with the main app.

I tried both using core data and user defaults, with the app group configured ofc, and for both I get errors about need write access. Is there any way around this or is it impossible to have a "save" feature on quicklook?
Save data from to app from quicklook extensions
 
 
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