It's a good question, I don't know why you're downvoted. Because the synchronization protocol (backed by Git) is operating in the background, web frontends are

It's a good question, I don't know why you're downvoted. Because the synchronization protocol (backed by Git) is operating in the background, web frontends are always just querying local data, so it's actually quite fast. You can try browsing the linked repository and see for yourself.