At any given point in time, there are settings that can be expressed in UCI that LuCI doesn't understand.
Moreover, some settings LuCI knows about can have values that LuCI doesn't understand.
The smart thing to do in such situation would be to not touch them.
That's not what LuCI does.
As soon as you open a pop-up for editing some type of entity and click "save" on that pop-up, all settings whose values LuCI didn't understand get reset to default.
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