All bonus levels to javelin while using tu’rani’s bident disappears when going between zones. So if you get lets say +3 to javelin, when entering a new zone, you get a popup saying “-3 skill points removed from javelin”, and you have to spend those points again.
Equipping tu’rani’s bident is also buggy when it comes to the levels. While in a town the levels are not changed. If you for example got +2 to all and +1 to physical, after equipping tu’rani’s bident the level of javalin does not go to +2 but stays at +3, even though the tag says lightning and not physical. Unequiping tu’rani’s bident now registers the correct levels and removes 1 point but gives you back the point since its now a physical skill. Equipping tu’rani’s bident while in an instance correctly removes the bonus point from physical immediately.