title: What is better in vue.js 2, use v-if or v-show?
body: <p>I'm working in a project with vue 2. I need to know in which case the performance is better: Use v-if or v-show?.
  I have a long list and each item's list has a form hidden that I need show and hide to click a button that has each item list.
  What is better a toggle class of v-show or add and remove the form with v-if?</p>