Should the hearth frame be built on top of the existing tile or should the tile be removed and anchored to the subfloor for restoring the wood burning fireplace?

Hey there! So, when we moved into our house, the previous owners had replaced the wood burning fireplace with an electric one. We’re thinking of bringing back the wood burning fireplace and putting in a hearth.

Do you think it’s okay to build the frame for the hearth on top of the existing tile, or do you think I should remove the tile and secure it to the subfloor instead?

Thanks for your help in advance!