I ran into a strange issue with redux-saga and the Redx DevTools browser extension.

I had a simple saga like this

export function* watchSetThing() {
    yield takeEvery('SET_THING', handleDoStuff);
}

but, when I manually dispatched a SET_THING action from the Redux DevTools extension, handleDoStuff was never called.

I was initially creating my store like this

const store = createStore(
    reducers,
    window.__REDUX_DEVTOOLS_EXTENSION__ && window.__REDUX_DEVTOOLS_EXTENSION__(),
    applyMiddleware(sagaMiddleware)
);

The reason I was having trouble is because the sagaMiddleware and the Redux DevTools extension aren't properly connected. My takeEvery call doesn't know that dispatches from the DevTools extension are happening.

I had to change my store to look like this instead

const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;

const store = createStore(
    reducers,
    composeEnhancers(applyMiddleware(sagaMiddleware))
);

and then everything worked properly.