How to listen to YouTube music with your screen off

One of my favourite music players is YouTube. Specifically, because when you select a song, you're offered a "Mix" as part of the suggestions on the video which queues a range of songs that are similar.

Note: You must have a YouTube account (Google account) to create and save playlists.

TL;DR Version:

Create playlists on YouTube (on Mobile or PC). Download Firefox for Android. Download Adblock Plus addon for Firefox for Android. Open YouTube in Firefox, head to your channel and play the playlist you previously saved.

Creating a mix based on one song

Search for a song that you want to listen to. Click on the "Mix" playlist on the right side of it. Click on the "Save Playlist" icon above the playlist.

For Mobile, you can do this process, too, through the YouTube app. The playlist appears underneath the video, rather than next to it, and the icon is on top of the playlist.

I would recommend creating several playlists for the various moods you're in. You can create custom playlists, too, and listen to them the same way you would these automated playlists.

Once you've sorted your playlists, there's a special way to play them with specific conditions:

You want to play these songs without being in the app - currently not possible without YouTube Red) You want to play these songs while also being able to turn the screen off.

Play your music using Firefox Browser for Mobile

Firefox for Mobile is the only platform that allows you to play media on your mobile device without being in the app. You can download Firefox for Android by clicking here.

A special feature in Firefox for Android, that isn't offered by other browsers, such as Chrome for Android - is the ability to have browser addons. One of those browser addons is an adblocker, meaning that you can listen to music uninterrupted and free of advertising. You can download the Adblock Plus addon for Firefox for Android by clicking here.

Enabling background data while screen is off

An issue I encountered while trying to listen to music with the screen off was that the music kept to turning off, but when putting the screen back on, the video started loading again and began playing. I concluded that this meant that there was an issue with downloading while the screen was off. I found that the cause was due to using battery saver mode. Here's how to fix that:

Head to Settings > Battery > Power Saving Mode

Alternatively, when in settings, search for Restrict background data which will immediately bring up the setting.

Once on this screen, enable the option Restrict all background data.

How to listen on your mobile

Open Firefox and head to YouTube.com. Go to your channel (on the far right of the top four icons) and find your playlists, click on the one you want and hit play.

You're set. Enjoy making playlists and listening to them free and uninterrupted the same way you would listen to Spotify.