I am using angular-ui-router 0.2.18 with angular 1.5.x. I cannot explain why my component $onInit fires twice (I do not think it is relevant to my problem, but I am also using webpack).
My routing:
myModule.config(function ($stateProvider) {
    $stateProvider
    .state('app.project', {
        abstract: true,
        url: '/project',
        template: '<ui-view/>'
    })
    .state('app.project.demo', {
        url: '/demo',
        template: '<my-component></my-component>'
    });
});
A barebone version of my component:
myModule.component('myComponent', {
    template: require('./my-component.html'),
    bindings: {},
    controller: function () {
        this.alert = function () {
            console.log("fires");
        };
        this.$onInit = function () {
            this.alert();
        };
    }
});
Somewhere in my application, the route change is triggered by <a ui-sref="app.project.demo"></a>.
The alert function fires twice when I click the link, but not when I reload the page. Maybe the controller is loaded twice on route change ?
I have tried everything listed on this SO question: combating-angularjs-executing-controller-twice, but without success.
What really puzzles me though, is that the issue disappears when I rename my state name without changing anything else:
'app.project.demos'works'app.projects.demo'works too (after changing'app.project'to'app.projects'of course)
What could be the explanation ?