ember.js - ember-bootstrap: Navbar component repeats itself 12 times -

i using ember-bootstrap's navbar example code in simple ember test app:

{{#bs-navbar |navbar|}}   <div class="navbar-header">     {{navbar.toggle}}     <a class="navbar-brand" href="#">brand</a>   </div>   {{#navbar.content}}     {{#navbar.nav |nav|}}       {{#nav.item}}         {{#nav.link-to "home"}}home{{/nav.link-to}}       {{/nav.item}}       {{#nav.item}}         {{#nav.link-to "navbars"}}navbars{{/nav.link-to}}       {{/nav.item}}     {{/navbar.nav}}   {{/navbar.content}} {{/bs-navbar}} 

however i'm having strange results; navbar showing 12 times in page. it's worth, toggle button doesn't either - might connected reason navbar appears 12 times. see following screenshot:

here steps took set project:

1. ember new bootstrap-test
2. inside /bootstrap-test:
   1. ember install ember-bootstrap
   2. ember g ember-bootstrap --bootstrap-version=4

here contents of ember-cli-build.js file:

/* eslint-env node */ 'use strict';  const emberapp = require('ember-cli/lib/broccoli/ember-app');  module.exports = function(defaults) {   let app = new emberapp(defaults, {     'ember-bootstrap': {       'bootstrapversion': 4,       'importbootstrapfont': false,       'importbootstrapcss': false     }   });    // use `app.import` add additional libraries generated   // output files.   //   // if need use different assets in different   // environments, specify object first parameter.   // object's keys should environment name , values   // should asset use in environment.   //   // if library including contains amd or es6   // modules import application   // please specify object list of modules keys   // along exports of each module value.    return app.totree(); }; 

finally, i'm using ember-cli version 2.14.2. figure out appreciated. thank you!

it might caused re-rendering due property update in didrender or didinsertelement hook. if that's case surely assertion error in console.

i first error, if there more no of errors reported in console. helped me lot in development.