Textures don't update in already open item creation tabs

When you go to add an item or a block or anything with a texture and make a texture using the tab and save it, it saves and is viewable in any tabs made after it was saved but going back to the item you created the texture for it only will show if you delete it and restart making it after the texture was saved. 

New textures don't appear in tabs opened before the texture was saved.