xfwm4 has a mousewheel-rollup feature, which is enabled by default. In my opinion it would be better if this feature would be *disabled* by default. The mousewheel-rollup feature causes many complaints from people who inadvertently perform a rollup of the active window, and then think that their application window has suddenly closed. Or they see the rolled-up window bar, but don't know how to restore it... I've never met anyone who actually uses the mousewheel-rollup on purpose, but I've heard many complaints from people about involuntary mousewheel-rollups. So changing the default to "disabled" seems an improvement to me. Experienced users can always enable it if they want to.
Well this needs a tweak setting first then.
Added tweak option in a99c18c.
Disabled by default in d8c3df3.