Unlike pausing, here we’re freezing the app to be sure that nothing will mess up the state (unless we’re dispatching actions explicitly from the Dispatcher or skipping actions or making any changes in our reducers)
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Mihail Diordiev

Is my understanding incorrect or is there some bug?

When practicing with the sample redux-devtools-extension/examples/counter, I clicked “Lock” button and then dispatch increment() action in “Dispatcher”. Nothing happened! The explicit dispatching doesn’t work.