[CLIENT] Deleting mastery pages in TeamBuilder does not remove them from the drop-down

I think the title is clear enough. So if you go in team builder and look at the mastery list you will obviously see the list of your mastery pages. But if you click on the edit button and delete some pages (I noticed the ones you delete must NOT be selected), when you come back the list will be identical! The deleted ones are still there, but if you quit the game and re-create or re-join they will disappear.

How to reproduce Go to profile / masteries and make sure you have a few pages there, with the first three deletable. I had about 20. Next, go to team builder and create a game. Choose your champion, lane and role then select the last page in masteries. Then go to edit and delete first 3 pages and return. Click on the drop-down and the deleted pages are still there! You can also select them, not very sure what happens if you start the game like that.