Fridge making loud clunk when compressor shuts off
If the external compressor mounts are good, then this is most likely to be internal mounts. And the problem with them is that's usually a replace, not a repair - while your food goes off.

The upside, it could keep running for ages with the clunk. I know of various ones with friends, and through online reports, that have lasted 10 or more years doing this.

But it could just fail one day without warning, so plan for a new fridge (or at least a new compressor)