An axe (of any type) will become stuck in your inventory after you use the axe to break any kind of block. This does not occur when using the axe to strip a block, when breaking blocks that do not reduce its durability (like grass, flowers, crops, etc.), or when the axe is enchanted with Unbreaking (of any level).

Steps to Reproduce:

1. Obtain an axe (any type)
2. Break any block with it
3. Go into your inventory and try to move the axe around

You'll notice the axe is now stuck in your inventory.

Workarounds:

• Drop the axe (only from your hotbar)
• Enchant the axe with Unbreaking (any level)
• Die
• Reload the world

I have also posted a video showcasing the bug: https://youtu.be/EIzPuvG_cB4