So I decided to check a schematic I’d drawn in v5.x after converting it to 6.0.x, and it pointed out an ERC error that had me double-checking the IC symbol against the datasheet.
I confirmed I’d made a mistake in my copy of the symbol and corrected it. Saved the symbol and re-ran ERC. The error that had caused me to re-check the symbol was gone, but in its place was a warning that the symbol in the library had changed.
I deleted the symbol from the schematic and placed a fresh copy from the library. The warning persists.
Now what?