Vuejs event modifiers
One of the best ways to see how .prevent and .self interact is looking at the output of the Vue compiler:
.prevent.self:
on: { "click": function($event){ $event.preventDefault(); if($event.target !== $event.currentTarget) return null; logger($event) }}.self.prevent
on: { "click": function($event){ if($event.target !== $event.currentTarget) return null; $event.preventDefault(); logger($event) }}The key difference between those 2 code blocks is inside the fact that the order of the operations matters, a .prevent.self will prevent events coming from its children, but doesn't run any code, but a .self.prevent will only cancel events directly created by itself, and ignores child requests completely.
Demo:
var app = new Vue({ el: '#appp', data: {log:[]}, methods: { logger(arg) { this.log.push(arg); } }});<script src="https://cdn.jsdelivr.net/npm/vue@2.5.13/dist/vue.js"></script><div id="appp" style="display: flex; flex-direction: row;"> <form @submit.prevent="logger('form')" style="width: 50%;"> <button> <p @click.prevent.self="logger('prevent.self')"> prevent.self <span>(child)</span> </p> <p @click.self.prevent="logger('self.prevent')"> self.prevent <span>(child)</span> </p> <p @click.prevent="logger('prevent')"> prevent <span>(child)</span> </p> <p @click.self="logger('self')"> self <span>(child)</span> </p> <p @click="logger('none')"> none <span>(child)</span> </p> </button> </form> <pre style="width: 50%;">{{log}}</pre> </div></div>