Uncaught (in promise) Error: Record does not start with a ":": from microbit import *
at validateRecord (ihex.ts:125:1)
at Module.getRecordType (ihex.ts:136:1)
at isMakeCodeForV1HexRecords (universal-hex.ts:342:1)
at isMakeCodeForV1Hex (universal-hex.ts:359:1)
at ProjectActions.load (project-actions.tsx:308:1)
Ah, this is in the isMakeCodeForV1Hex check that we already do in an error handling path so it doesn't get error handling itself when it fails. It just needs to swallow the error.
Seen in the wild via logging.
Production stacktrace: