permitted file extensions for upload

neue medienordnung plus
  last edited: Mon, 19 Nov 2018 05:35:27 +0100  
I permitted in "Individual Permissions" for my connection Klaus the option
Can upload/modify my file storage and photos

Klaus can upload png files, but the XCF files has the size 0 kb. I can upload XCF fies in my cloud. Which file extensions are permitted for upload for strangers accounts?

!@Hubzilla Support Forum

Workaround -> Klaus can zipped xcf files.