If you need to quickly edit or view a swagger/openapi spec, you can use the mighty swagger editor: https://github.com/swagger-api/swagger-editor

For a quick way to run it, use docker to run the editor itself:

docker pull swaggerapi/swagger-editor
docker run -d -p 8080:8080 swaggerapi/swagger-editor

Then open your browser on localhost to use the webapp.

xdg-open http://127.0.0.1:8080