[Fernando Tella]

Open a saved material > tweak some things > try the wizard menu > a menu asks if I want to save the changes to the original material > click NO > the original material is overwritten with the result of the wizard

Notice I never clicked to save the material but I've lost the original. That's not a proper behaviour for a well educated material editor.

[Fernando Tella]

Nobody got this problem?

[Mihai]

Confirmed.

[Bubbaloo]

Confirmed, this happened to me a few times, but I didn't know why.