External HDMI display not detected after boot

Question

I have a 4k laptop and 4k external display connected through HDMI.

If I connect the display, then boot up the system, it detects it just fine, and works. But when I connect it after boot, it doesn't get detected. The "Detect Displays" button in System Settings does nothing. How to make it detect it?

If the automatic detection after boot is currently buggy, is there a command to redetect displays? (Presumably the same way the system does on boot?)

• OS: elementary OS 0.4.1 Loki x86_64
• Kernel: 4.13.10-041310-generic

I also have the elementary-os/daily PPA installed.

Answer 1

I don't know why or when, but it sorted itself - probably one of the daily patches. Thanks, eOS team!