I noticed that when I open a replay, my character displays armor weirdly. I am testing this using a replay recorded in 1.8, which perfectly works in 1.16 except for this bug. This bug ONLY occurs for MY character, not for any other players in the replay.
However, this bug does NOT occur in the 1.14 version.

1.14

1.16

In 1.16, spectating and pressing my inventory key opens up this, and shows that the chestplate piece is being duplicated onto the head piece, with the metadata being identical. Also note in the inventory the rest of the armor shows up, but in action it does not. Again, none of this is present in 1.14 or prior.

I would also like to amend that it wont show the item i'm supposed to be holding as well. Again, works for every other player, just not mine.

If you can look into this soon I would appreciate because I unfortunately can't just go back in versions with what I am doing with this replay.