If I upload a custom background to my dashboard via the UI, the background naturally changes immediately. However, if I replace the file with a different background through an automation, the dashboard still shows the old background. How can I get HA to clear/update its cache or detect that the background has changed? I need to do this frequently since the background image is changed every hour.
Try using a random version:
background-image: url('/local/images/my_image.jpg?v=1234567');
Can be composed based on current timestamp.