[SOLVED] How to remove texture data from materials asset before any load at app startup

In the configure function (before preload) i do this :

var materials_dyn = app.assets.findByTag("material_dyn");
        for (var i = 0; i < materials_dyn.length; i++) {
            materials_dyn[i].data.diffuseMap = null;
            materials_dyn[i].data.opacityMap = null;
            materials_dyn[i].data.glossMap = null;
            materials_dyn[i].data.normalMap = null;
            materials_dyn[i].data.metalnessMap = null;

but i can still see all textures in my app, did I miss something?

I tried with resource instead of data but no result

EDIT : ok I found another solution for my problem.