Implemented half-working capture button. Needs some fine tuning

src/vue/components/CaptureButton.vue

+<template>
+  <input type="button" @click="capture"/>
+</template>
+
+<script>
+  import $ from 'jquery'
+  export default {
+    name: 'capture-button',
+    props: {
+      target: {
+        type: String,
+        required: true
+      }
+    },
+    methods: {
+      capture () {
+        const target = document.querySelector(`${this.target}`)
+        if (!target) {
+          throw new Error('CaptureButton could not find target for given selector.')
+        }
+        const svgs = document.querySelectorAll(`${this.target} svg`)
+        svgs.forEach(svg => {
+          svg.setAttribute('version', '1.1')
+          svg.setAttribute('xmlns', 'http://www.w3.org/2000/svg')
+          svg.insertAdjacentHTML('afterbegin', this.getDefs())
+        })
+        $(target).wrap('<div id="fjs-capture-container"></div>')
+        const b64 = window.btoa(window.decodeURIComponent(window.encodeURIComponent(target.innerHTML)))
+        const blob = this.b64toBlob(b64, 'image/svg+xml')
+        const blobUrl = window.URL.createObjectURL(blob)
+        const a = document.createElement('a')
+        a.style = 'display: none'
+        a.href = blobUrl
+        a.download = 'capture.svg'
+        a.click()
+        window.URL.revokeObjectURL(blobUrl)
+        // TODO remove defs again
+      },
+      b64toBlob (b64Data, contentType, sliceSize) {
+        contentType = contentType || ''
+        sliceSize = sliceSize || 512
+        const byteCharacters = window.atob(b64Data)
+        const byteArrays = []
+        for (let offset = 0; offset < byteCharacters.length; offset += sliceSize) {
+          const slice = byteCharacters.slice(offset, offset + sliceSize)
+          const byteNumbers = new Array(slice.length)
+          for (let i = 0; i < slice.length; i++) {
+            byteNumbers[i] = slice.charCodeAt(i)
+          }
+          const byteArray = new Uint8Array(byteNumbers)
+          byteArrays.push(byteArray)
+        }
+        return new window.Blob(byteArrays, {type: contentType})
+      },
+      getDefs () {
+        const rules = []
+        for (let sheet of document.styleSheets) {
+          for (let rule of sheet.cssRules) {
+            if (rule instanceof window.CSSStyleRule) {
+              rules.push(rule.cssText)
+            }
+          }
+        }
+        return `<defs><style type="text/css"><![CDATA[${rules.join('')}]]></style></defs>`
+      }
+    }
+  }
+</script>
+
+<style lang="sass" scoped>
+
+</style>