Bug Report

Ionic version:

[x] 4.x

Current behavior: Web preview enters debug mode after trying to access a page from the side menu

Expected behavior: Not enter debug mode. I’m not really sure if that’s intended or not.

Steps to reproduce: Trying to access a page through the side menu causes the application to enter debug mode. This happens only on the first time. It just happened on web preview, but didn’t test on native run. The debug apparentely points to a file inside node modules. The path is as follows:

node_modules/@ionic/core/dist/esm-es5/chunk-c90aaa66.js

and the line indicated is line 40

var assert = function (actual, reason) {
    if (!actual) {
        var message = 'ASSERT: ' + reason;
        console.error(message);
        debugger; // tslint:disable-line
        throw new Error(message);
    }

It also throws this error during debug: ASSERT: _before() should be called while animating

And this one after debug: Unhandled Promise rejection: ASSERT: _before() should be called while animating ; Zone: <root> ; Task: Promise.then ; Value: Error: ASSERT: _before() should be called while animating

Related code:

var assert = function (actual, reason) {
    if (!actual) {
        var message = 'ASSERT: ' + reason;
        console.error(message);
        debugger; // tslint:disable-line
        throw new Error(message);
    }

Other information:

Ionic info:

Ionic:

   Ionic CLI                     : 5.4.4 (/home/rodrigo/.nvm/versions/node/v10.15.3/lib/node_modules/ionic)
   Ionic Framework               : @ionic/angular 4.7.4
   @angular-devkit/build-angular : 0.13.9
   @angular-devkit/schematics    : 7.3.9
   @angular/cli                  : 7.3.9
   @ionic/angular-toolkit        : 1.5.1

Cordova:

   Cordova CLI       : 9.0.0 (cordova-lib@9.0.1)
   Cordova Platforms : android 8.1.0
   Cordova Plugins   : cordova-plugin-ionic-keyboard 2.1.3, cordova-plugin-ionic-webview 4.0.1, (and 14 other plugins)

Utility:

   cordova-res : 0.6.0 (update available: 0.8.0)
   native-run  : 0.2.8 (update available: 0.2.9)

System:

   Android SDK Tools : 26.1.1 (/home/rodrigo/Android/Sdk)
   NodeJS            : v10.15.3 (/home/rodrigo/.nvm/versions/node/v10.15.3/bin/node)
   npm               : 6.11.3
   OS                : Linux 4.15