Error on setting value

[aquadk]

I'm submitting a ... (check one with "x")

[x ] Bug report => search github for a similar issue or PR before submitting
[ ] Feature request
[ ] Other, please describe

Tell about your platform

• flatPickr version : 4.x.x
• Vue.js version : 2.6.x
• Browser name and version : Chrome|Firefox|Safari x.x.x
• This package version : x.x.x

Current behavior
Get this error in console:
[Vue warn]: Error in nextTick: "TypeError: Cannot read property 'value' of null"
stacktrace:

warn | @ | vue.runtime.esm.js:619
-- | -- | --
  | logError | @ | vue.runtime.esm.js:1874
  | globalHandleError | @ | vue.runtime.esm.js:1869
  | handleError | @ | vue.runtime.esm.js:1835
  | (anonymous) | @ | vue.runtime.esm.js:1972
  | flushCallbacks | @ | vue.runtime.esm.js:1896
  | Promise.then (async) |   |  
  | timerFunc | @ | vue.runtime.esm.js:1923
  | nextTick | @ | vue.runtime.esm.js:1980
  | Vue.$nextTick | @ | vue.runtime.esm.js:3490
  | onInput | @ | vue-flatpickr.min.js:141
  | invokeWithErrorHandling | @ | vue.runtime.esm.js:1847
  | invoker | @ | vue.runtime.esm.js:2169
  | original._wrapper | @ | vue.runtime.esm.js:6855
  | triggerEvent | @ | flatpickr.js:1980
  | setDate | @ | flatpickr.js:1860
  | value | @ | vue-flatpickr.min.js:167

Expected behavior
/**
* Watch for value changed by date-picker itself and notify parent component
*
* @param event
*/
onInput(event) {
// Lets wait for DOM to be updated
this.$nextTick(() => {
event.target && this.$emit('input', event.target.value);
});
},

Can be solved by checking for target is assigned

Minimal reproduction of the problem with instructions
Error when setting value on component.

[ankurk91]

Could not reproduce the error described.

https://jsfiddle.net/nzypq8gw/

[Silentscripter]

The bug seems to happen when the component is used in a vue app that is wrapped inside a webcomponent. A pull request to fix the issue has been provided and linked.