you are wrong. te bug happens to me on all crafts, most of them are on 100, and i can not even learn new recipes ( masonry ). as i already said to guidesariel, its not happening when i gain exp/ get lvlups/ learn recipes. its completely random.
usual when the bug happens it just deselect the recipe, but its also possible the recipe is still selected and all mats & tools are deselected.
its not happening on the test server because the backup on it was made before the last maintenence ( about 4 days ago?! ) and the bug didnt exist before.