Git message type on library update - node.js

Question

I make my own react boilerplate and come until updating packages. So I've update react across major version (v15x to v16x), and change my code on a module file called injectReducer. So what i've changed in injectReducer is from this:
static contextTypes = {
store: PropTypes.object.isRequired,
};
to this:
static contextType = ReactReduxContext;
Now I think this doesn't do any breaking changes on my boilerplate, because the use of the module still the same (backward compatible). But what about the package I've updated? Should any library updated across major is considered breaking changes? What about minor updates?
Here is my full code of injectReducer:
import React from 'react';
import { ReactReduxContext } from 'react-redux';
import hoistNonReactStatics from 'hoist-non-react-statics';
import getInjectors from './reducerInjectors';
export default ({ key, reducer }) => (WrappedComponent) => {
class ReducerInjector extends React.Component {
static WrappedComponent = WrappedComponent;
static displayName = `withReducer(${(WrappedComponent.displayName || WrappedComponent.name || 'Component')})`;
static contextType = ReactReduxContext;
injectors = getInjectors(this.context.store);
componentWillMount() {
const { injectReducer } = this.injectors;
injectReducer(key, reducer);
}
render() {
return <WrappedComponent {...this.props} />;
}
}
return hoistNonReactStatics(ReducerInjector, WrappedComponent);
};

Answer 1

But what about the package I've updated? Should any library updated across major is considered breaking changes?
That is the idea behing the major version in semver
when you make incompatible API changes
Except I would consider it does not involve just the API.
See as an example "Semantic Versioning, Go Modules, and Databases" (just to illustrate the kind of non-API change which would still warrant a major version bump)
Basically, if any client of your library has work to do in order to adapt to the new version... your change should be considered major.
If not: minor.