Setting Keep window below preference immediately makes Prefs window drop in window stack (v1.2.0)

[Francis Chin]

Some of the prefs in v1.2.0 have been made dynamic (they apply immediately rather than after the OK dialog button is clicked). One of these is the "Keep window below" preference.

Unfortunately while this works, this also causes the Preferences dialog to drop with the main window in the window stack, which leaves it hidden from the user if they have other windows open at the same time. This is a problem as the user may have been setting other preferences in the dialog, and will not have expected this behaviour as they still expect to click OK/Cancel. Even if they weren't in the middle of setting preferences, certain actions on the main window are blocked until the Preferences dialog is found and dismissed.

I think this particular preference should be reverted back to the old behaviour.