When using force upgrading (or “optimisation” as it appears to be called), data is automatically converted to the latest version. However, the new data version tag is not written to for entity and poi data. When the data is loaded next, it will be converted again. This specifically causes text component converters to error.
Environment
Irrelevant
Does this fix address the issue of renamed items (e.g., via anvils) losing their names after a world has been optimized? From the description, it seems related to text component conversion errors, but I just wanted to confirm.