I tried to figure out how to change the default font in #Outlook (being annoyed that I would have to change it in 2 places if doing it manually through File > Options > Mail > Compose messages > Stationery and Fonts for New mail messages and for Replying or forwarding messages)
I asked #MSCopilot
It proposed the #PowerShell command
Set-MailboxMessageConfiguration -Identity $userPrincipalName -FontName $fontname
Turns out that is wrong. Correct is
Set-MailboxMessageConfiguration -Identity $userPrincipalName -DefaultFontName $fontname
While the AI help me to get on the right track, this demonstrates how dangerous (blindly) trusting the AI result is.
If this wouldn't have been easily verifiable (because it was basically a single line of code) and didn't fail it could have caused any serious of problems.