I’m using react v16.13.0 and react-router v5.2.0, do you have a update instruction?
Just check the breaking-changes part of the announcement. If you don’t think you are affected, proceed with the upgrade. We just run our e2e tests after the upgrade and everything passed (we run it before during the rc releases so we have confidence that nothing breaks)
Found one issue upgrading so far: https://github.com/meteor/react-packages/issues/299