Get rid of new toolbar and menu after installing v12

I have my own toolbar and menu (with specific names) and want to have my toolbar/menu instead of the build in ones.

Default toolbars (and menu) replaced my toolbars in all layouts. How can I change to my toolbars in all saved layouts?

What does it mean if toolbar checkbox in customize dialog has "undefined" state, ie. it's neither enabled or disabled? I can't completely disable default toolbars (they toggle between undiefined state and enabled) and (I think) it causes it's shortcuts to be always enabled, even if "always enable this toolbar's keys in Listers" is disabled for that particular toolbar (for both, default toolbar and default menu).

See: [Your old toolbars are still there after you upgrade)

The intermediate checkbox state means the toolbar is on in some windows and off in others. Since toolbars are now independent in each window, it's often better to manage them in a lister than the Customize window. Save the result as the default toolbar set, as explained in the FAQ linked above.

I made my old toolbars the default set.

Now, I have only one lister open and if I go to customize dialog, the default toolbars are still in intermediate state.
The underlying problem I want to solve is if I go to Keys tab in customize dialog, I see all shortcuts, even those from those old, disabled toolbars (which I never use). It's confusing when I see my shortcuts duplicated and in red (which usually means that two commands use the same shortcut, which is something bad).

None of the toolbars have "always enable this toolbar's keys in Listers" turned on?

Do you still see the duplicates even after fully exiting Opus (via File / Exit Directory Opus)?

Which keys are duplicated? Can we see a screenshot?

Only my toolbars have selected the option, but I have them enabled anyway.

Fully exiting Opus solved the problem.

Thanks a lot!