Unable to use Handler with vue-quill-editor - vuejs2

Question

What I'm trying to do?
Use a Handler that allow me insert an image by URL, the reason for this is to not use too much space in the Database.
What version of Vue I'm using?
Vue 2
What is not working?
When I add the handler, quill toolbar doesn't identify my custom toolbar, and it adds all the options, the console is throwing me the next error: "[Vue warn]: Error in data(): "ReferenceError: showImageUI is not defined".
Also "this.quill.insertEmbed()" is not working, the console threw me this: "Uncaught ReferenceError: Quill is not defined" (this pass when I change the Handler Image value, I'll let the second option at the final)
<template>
<div class="addBlog">
<h1>Add New Blog</h1>
<quill-editor v-model="content" :options="editorOptions" ref="myQuillEditor"/>
</div>
</template>
<script>
import 'quill/dist/quill.snow.css';
import { Quill, quillEditor } from 'vue-quill-editor';
export default {
name: 'AddBlog',
components: {
quillEditor
},
data: () => ({
title: '',
category: '',
content: '',
editorOptions: {
theme: 'snow',
debug: 'info',
placeholder: 'Type your post...',
readOnly: true,
modules: {
toolbar: {
container: [
['bold', 'italic', 'underline', 'strike'],
['link', 'image', 'video']
],
handlers: { image: showImageUI }
}
}
},
// debug: 'info',
// placeholder: 'Type your post...',
// readOnly: true,
// theme: 'snow'
// },
delta: undefined
}),
methods: {
showImageUI() {
var range = this.quill.getSelection();
var value = prompt('please copy paste the image url here.');
if(value){
this.quill.insertEmbed(range.index, 'image', value, Quill.sources.USER);
}
}
},
watch: {
content() {
this.delta = this.$refs.myQuillEditor.quill.getContents();
}
}
};
</script>
And here I let you the code(the second option) where I used directly the function into the handler:
editorOptions: {
theme: 'snow',
debug: 'info',
placeholder: 'Type your post...',
readOnly: true,
modules: {
toolbar: {
container: [
['bold', 'italic', 'underline', 'strike'],
['link', 'image', 'video']
],
handlers: { image: function imageHandler() {
var range = this.quill.getSelection();
var value = prompt('please copy paste the image url here.');
if(value){
this.quill.insertEmbed(range.index, 'image', value, Quill.sources.USER);
}} }
}
}
},