Hello I think found a bug that looks very similar to this: https://github.com/dotansimha/graphql-code-generator/issues/1762, except its with interfaces instead with unions.

I made small repo with this error here: https://github.com/panzelva/gql-gen-interface-issue
Fixed in 1.4.0 馃帀
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Fixed in: https://github.com/dotansimha/graphql-code-generator/commit/d4804df119feb6ecdcd8593a7f81d398bb03419b