Installing libicu worked for me on clean new f41 boxbuddy container. I recommend try to start over with a new container and install libicu before megasync. Maybe megasync install is conflicting somehow.
I tried several times with and without the devel and doc packages in both the quay.io/fedora/fedora:41 and the quay.io/fedora/fedora-toolbox:41 images. I could not reproduce your error. It looks like it is failing while trying to unpack the rpm. Why that is, I donβt know. Could be disk space, corrupted download, package signing key, etcβ¦ "Unpack error: " is not very helpful error message. See if you can get a more verbose output or do a web search on why extract fails. You can try installing some other package (e.g. ffmpeg) as a test to see if it is just this package that has problems. If not, it is a more general problem to investigate. Check if there are any useful error logs in /var/log/dnf5.log file.
Update: i can sudo dnf install libicu in boxbuddy under root (su) no issues and installs megasync without a hiccup. But unable to execute megasync in normal user mode. Very frustrated with this issue. I did a fresh install on laptop aurora and installed megasync straight away and worked no problems. But on my main desktop i get this error even on a fresh install and no idea why. I use the latest aurora iso with nvidia on the desktop and my laptop is intel gpu