Typescript does not import JSON and throws Type error

[MattyBalaam]

Is this a bug report?

Yes

Did you try recovering your dependencies?

Yes

Which terms did you search for in User Guide?

JSON, import JSON

Environment

System:
OS: macOS High Sierra 10.13.6
CPU: x64 Intel(R) Core(TM) i5-7360U CPU @ 2.30GHz
Binaries:
Node: 10.11.0 - /usr/local/bin/node
Yarn: 1.10.1 - /usr/local/bin/yarn
npm: 6.4.1 - /usr/local/bin/npm
Browsers:
Chrome: 70.0.3538.77
Firefox: 63.0
Safari: 12.0
npmPackages:
react: Not Found
react-dom: Not Found
react-scripts: Not Found
npmGlobalPackages:
create-react-app: Not Found

Steps to Reproduce

1. add a json file to project
2. add import json from './test.json'; to another file
3. start compilation

Expected Behavior

Json file is imported into app and become JS object - which works in a refular .js CRA project.

Actual Behavior

Type error: Cannot compile namespaces when the '--isolatedModules' flag is provided. TS1208

Reproducible Demo

https://github.com/MattyBalaam/json-typescript-CRA-bug-report

1. install dependencies
2. run start

[Timer]

/cc @brunolemos