"Reset all toolbars and controls" in Safe Mode dialog doesn't work

[gracious1]

When you select "Reset all toolbars and controls" in the Safe Mode dialog, like so:

...presumably this is the equivalent of the "Restore Default Set" button in the Customize Toolbar dialog. But this doesn't seem to be case.

To test...
1. I created a new, clean profile, and then created a toolbar called Extra Toolbar.
2. I randomly put buttons in the Extra Toolbar from the Customize Toolbar dialog. I also put other random buttons in the Navigation Toolbar.
3. I selected Help >> Restart with add-ons disabled and clicked Restart in the dialog box.
4. I made the selection illustrated above in the Safe Mode dialog box and hit "Make Changes and Restart".
Result: Extra Toolbar reappeared with buttons intact. Additional buttons in Navigation Toolbar also remained.

• Pale Moon 27.3.0
• Ubuntu 14.04.5
• No add-ons installed

[GMforker]

See viewtopic.php?f=37&p=113580#p113580.