Upload of large files fails


i am currently using the Docker Nextcloud image 18.0.3 on my Raspberry Pi 4 4GB with Traefik as a reverse proxy.

When I upload a large file (8 GB) via web browser (Firefox) I get the following error message while processing the data:

Error while copying file to target location (copied bytes: 0, expected filesize: -1 )

A file with for example 1 GB is no problem. Furthermore the upload speed drops from 12 to 2 MB/s every now and then.

Where is the problem?

Version: 7.3.16
Working memory limit: 512 MB
Maximum execution time: 3600
Maximum upload size: 2 MB

Version: 10.0.38