Support user control or saving of new window dialog preference

[kkoreilly]

Describe the feature

For value buttons, the user can shift click to open the dialog in a new window. It would be nice if there was either a user setting to default to opening dialogs in a new window, or if it automatically remembered the user preference such that a dialog you previously opened with shift click would open in a new window going forward.

We could use the window geometry for automatic remembering: if a dialog name is not in the window geometry file, then it should not be opened in a new window. If it is in the file, then we can check a stored value in the file as to whether it should be in a new window (we need to check a value so that it can update that value to false when you open it not in a new window after you first opened it in a new window, using shift click again to negate the previously saved behavior).

Relevant code