Make sure menu ref is set before accessing this.menu.contains

[Bartozzz]

On line 204 in /src/dropdown.js you are trying to access this.menu.contains. This will throw an error when this.menu is not set.

if (isInput && (key === ' ' || key !== 'Escape' && _this.menu.contains(target)))

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Logs from my project:

Uncaught TypeError: Cannot read property 'contains' of null
    at Dropdown._this.handleKeyDown (Dropdown.js:209)
    at HTMLUnknownElement.callCallback (react-dom.development.js:147)
    at Object.invokeGuardedCallbackDev (react-dom.development.js:196)
    at invokeGuardedCallback (react-dom.development.js:250)
    at invokeGuardedCallbackAndCatchFirstError (react-dom.development.js:265)
    at executeDispatch (react-dom.development.js:571)
    at executeDispatchesInOrder (react-dom.development.js:596)
    at executeDispatchesAndRelease (react-dom.development.js:695)
    at executeDispatchesAndReleaseTopLevel (react-dom.development.js:704)
    at forEachAccumulated (react-dom.development.js:676)
    at runEventsInBatch (react-dom.development.js:844)
    at runExtractedEventsInBatch (react-dom.development.js:852)
    at handleTopLevel (react-dom.development.js:5030)
    at batchedUpdates$1 (react-dom.development.js:21425)
    at batchedUpdates (react-dom.development.js:2247)
    at dispatchEvent (react-dom.development.js:5110)
    at react-dom.development.js:21482
    at Object.unstable_runWithPriority (scheduler.development.js:255)
    at interactiveUpdates$1 (react-dom.development.js:21481)
    at interactiveUpdates (react-dom.development.js:2268)
    at dispatchInteractiveEvent (react-dom.development.js:5086)