My initial guess was that sudo would eat up the echo’d foo as the password. Maybe sudo works differently when invoked via zsh?

Can’t reproduce.

16:22:48:~/tmp$ echo foo | sudo tee newfile
[sudo] Passwort für bleistift2:         
foo

16:23:02:~/tmp$ ls -l newfile
-rw-r--r-- 1 root root 4 Feb 23 16:22 newfile

The issue is still open. https://github.com/ventoy/Ventoy/issues/2795

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