How to restore Mapsforge Style's default values for options ?

[LaurentG]

A Mapsforge Theme may have several Style, and for each of these styles, there may be several options.
In Theme's definition, a default value exist for each of these options, that is the value taken by the option the first time the Theme is used.

My question is very simple : Is there a mean, in OruxMaps, after having changed one of several of these options, to restore all of them to their Default value ?

I've not found anything in the various menus, and I also tested to clean OruxMaps's cache, and also user managed caches in the app (raster, online, etc...) but I never went back to the default values of Mapsforge Theme options.

Is there another way of doing I missed ?

PS : BTW, if an option has the same internal name in two or more completely separate Themes, setting its value in a Theme sets it also in other Theme using it....