*Note* I had to select the affected version to be 1.20.6, but the version I was on was 1.20.4. I am unfamiliar with this website, so I don't know if I did something wrong.

The shield breaks extremely quickly if a player eats and the player then pauses the game right when the shield is activated.

This has only happened to me once, but to recreate it, I'd assume you'd need to do, is have a shield in your offhand, food in your main hand, eat, and open the pause menu right when the player finishes eating so the shield is activated while in the pause menu, and have a mob attack you. I don't know if this only works with magma cubes, which is what broke my shield.