Most ember apps when created new or that are existing all along have phantomJS configured for running tests. phantomJS runs a little flaky for some tests that involve keyboard events. And phantomJS is no longer actively maintained due to the arrival of Google Chrome headless support.
Link to this sectionStep 1: Installing Google Chrome in Linux machines
You may also refer: https://www.tecmint.com/install-google-chrome-in-debian-ubuntu-linux-mint/ if you face any issues with installing Google Chrome with the above steps.
Link to this sectionStep 2: Setting up Chrome headless for QUnit instead of phantomJS
Remove testem.json if you have it configured, and move the contents to testem.js (though this is not mandatory, testem itself throws a warning when you have both). Add the following in the testem.json file and remove phantomJS configurations.
Link to this sectionStep 3: Debugging in dev for visual representation
Link to this sectionFor more inputs on Google chrome headless
Link to this sectionWhy Chrome headless and why not phantomJS
While headless chrome might be able to replace PhantomJS for many use cases that doesn't necessarily mean the APIs will - news.ycombinator.com
Link to this section[Announcement] Stepping down as maintainer
"…PhantomJS is no longer maintained anymore. I guess we will see and replacement…" github.com