In the web player (which still uses Flash?) I've checked 'Play open.spotify.com URLs in desktop app'. In the app I've switched on 'Allow Spotify to be opened from thew web'.
But when I enter an open.spotfify.com URL in any browser (Safari, Firefox, Chrome), it still doesn't launch the app automatically. Instead it keeps on playing that track in the web player.
I've already tried re-installing the Spotify app and rebooting my computer. Also when I enter an open.spotify.com URL it changes 'open' to 'play'. But with the same result. Both open.spotify.com and play.spotify.com won't open the Spotify app automatically. Even when it is set to do so in both the web player and the app.
I'm using Mac OSX and I've tried Safari, Chrome and Firefox. All fully updated. But with the same result: when I enter an open.spotify url it plays the song in the browser and won't open the Spotify app.
For now, you'll be able to use a new web player here. No worries, you'll still be able to keep this setting by going to your desktop Spotify app > Startup and Window Behaviour > Allow Spotify to be opened from the web. In the meantime, we've gone ahead and passed your feedback on the functionality of the feature on the old web app to the right team.
If you ever need us again, let us know. We're always here to help.