React useFocus Hook Offers One-Line Focus State Tracking and Control

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A new custom React hook called useFocus, part of the @reactuses/core library, lets developers track and control element focus state with a single line of code. The hook returns a live isFocused boolean and a setter function that can programmatically focus or blur any element, covering both observation and control in one API. It addresses known limitations of native browser tools like document.activeElement, which provides only a static snapshot, and autoFocus, which fires just once at mount. Hand-rolled focus listeners are prone to bugs such as missed late-mounting elements, incorrect initial state, and repetitive boilerplate across form fields. The hook handles these edge cases internally, including support for lazy element references that re-resolve as the DOM changes.

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