Items in inventory, items bar and hand display as grey square, enchanted items have purple enchanted texture. 

Affected items include:

• Wooden and iron doors
• Golden apples/carrots, glistening watermelons, bread, beetroot soup, cookie, cake
• Most dyes
• Iron, gold and diamond armour, horse armour and tools, leather armour is a brown square
• Bows, plain arrows, flint and steel, fishing rods, maps, sticks, torches, bucket, bowl, pot, cauldron, brewing stand, armour stand, mine carts, hopper, comparator, firework rockets, boats, lead, books
• Coal, diamond, iron/gold ingots and nuggets, emerald, leather
• Fire charge, blaze powder, magma cream, eye of ender

Also dogs and hostile mobs are just black and red outlines.