Fread(): file created in the system's temporary directory at /var/www/nextcloud/apps/files_external/3rdparty/icewind/streams/src/Wrapper.php#91

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5

sys_temp_dir = /media/myCloudDrive/ncdata/tmp
which is the same path set in config.php.

I guess I will have to reinstall nextcloud-client as suggested in HEADERS on invalid stream