Hello,
I use a usb-c hub to connect my macbook pro to an external monitor via HDMI and it works fine.
However, when I use the same hub while not being connected to any external device, my macbook detects an external display. This is extremely annoying as some windows are sent to this second (non existing) monitor and disappear from the main display.
How can I fix this issue ?
The typical way two displays (one built-in, one external) are used is called "extended desktop":
when you disconnect the external display, it should go dark and no data should be sent to it. I don't understand why that is not working correctly.
but to work around, you could set your displyas to [√] Mirror displays. This computes a compromise resolution that both displays appear to be able to use, so your built-in display resolution may change. This may or may not be acceptable, but would look like this:
note that the TWO blue Icons are nearly superimposed on each other -- leaving only enough difference to drag them apart.
The keyboard shortcut to TOGGLE this mode is Command-BrightnessDown.
The typical way two displays (one built-in, one external) are used is called "extended desktop":
when you disconnect the external display, it should go dark and no data should be sent to it. I don't understand why that is not working correctly.
but to work around, you could set your displyas to [√] Mirror displays. This computes a compromise resolution that both displays appear to be able to use, so your built-in display resolution may change. This may or may not be acceptable, but would look like this:
note that the TWO blue Icons are nearly superimposed on each other -- leaving only enough difference to drag them apart.
The keyboard shortcut to TOGGLE this mode is Command-BrightnessDown.
to get a Mac display to become active, you need the Mac to query the display, and the display to answer with its name and capabilities. Otherwise, the display will not be shown as present, and no data will be sent to the display. "No signal detected" is generated by the DISPLAY, not by the Mac.
This query is only sent at certain times:
• at startup
• at wake from sleep — so momentarily sleeping and waking your Mac may work
• at insertion of the Mac-end of the display-cable, provided everything on that cable is ready-to-go
• on invoking Option-(Detect Display) button in Displays preferences (from another display)
so try doing some of those things and see if the display comes alive, in the proper orientation and number of actual displays connected.
exactly what make & model Hub?
what model-year MacBook Pro?
what version MasOS?
I am using an urban factory hub usb-c 10 in 1 on a MacBook Pro (13-inch, 2017, Two Thunderbolt 3 ports) with MacOs Monterey 12.2
Usb-C hub detects a monitor when there is none
