The browser tab for open.spotify.com must remain open for notifications to appear.
As of version v0.4.0 a browser action icon will also show the currently playing song with track controls when clicked.
=== FEATURES ===
WEB NOTIFICATIONS FOR CURRENT SONG:
• Show web notification with song title, artist, and album art
• Notification is shown when open.spotify.com is opened and when song changes
BROWSER ACTION WITH SONG PREVIEW AND CONTROLS
• Browser action icon will show currently playing song with controls to play/pause/change track
• Clicking links in the browser action popup window will focus the Spotify tab and show the album or artist clicked
• Ctrl+Shift+S: Show browser action with song preview
• Ctrl+Shift+Space: Toggle Play/Pause for current song from anywhere in the browser
• Ctrl+Shift+X: Show notification for current song from anywhere in the browser
• Keyboard shortcuts may be changed on the chrome://extensions/ page by strolling to the bottom of the page and clicking "Keyboard Shortcuts"
PLEASE REPORT BUGS OR FEATURES REQUESTS ON GITHUB. I don't regularly check comments on the web store.
• Feature: Add track controls to browser action
• Feature: Add links to browser action to jump to album or artist
• Feature: Add browser keyboard shortcut to show browser action (default: Ctrl+Shift+S)
• Feature: Add browser keyboard shortcut play/pause track from any tab (default: Ctrl+Shift+Space)
Feature: Add browser keyboard shortcut show notification from any tab (default: Ctrl+Shift+X)
• Bugfix: Don't show multiple notifications if rapidly changing track
• Bugfix: Fix browser action doesn't work if notifications are not granted
• Bugfix: Fix cover art scaling in browser action popup
• Security: Replace innerHTML calls with textContent
• Feature: Implement browser action to show currently playing song
• Performance: Replace recursive setTimeout call with MutationObserver