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tswhy‽

A community effort to enrich TypeScript diagnostics.

TS1060

The first parameter of the 'then' method of a promise must be a callback.

This is caused by the global Promise not having a compatible signature to support async/await downlevel emit.

Fix: Issue with promise library.

Either the 3rd party promise library cannot be used with TypeScript to down level emit async/await or there is a configuration issue with the library that is not allowing TypeScript to understand it will work. Consult the current documentation for the 3rd party promise library.