Can I disable drag and drop in opus

Can i disable drag and drop in opus 9 to prevent moving files and directories inadvertently?

In Opus 10 the option is: Preferences / File Displays / Options / Allow drag and drop into sub-folders (without a qualifier key held down)

I think it was in Opus 9 as well, maybe in the same place. If not, type "drag and drop" into the Preferences window's search box and it should find it.