Uploading with ST-Link to Generic STM32F103C series board prevents Serial.printl

When I use "Generic STM32F1 series" board with Board part number: "BluePill F108C8 (128k)", and USB support = Nothing, and Upload method: "STLink", I can use Serial output at runtime. If support is not "Nothing", there's no output on the console.

I have tried to do the same with "Generic STM32F103C series" board, and Upload method: "STLink". At runtime, I cannot make output from Serial.println go to the console.

What am I doing wrong ?

I've found something new (and strange). After flashing a sketch with ST-Link upload method, I cannot see console serial output when using ftdi. But I can see this output using usb cable, and /dev/cu.usbmodem14201 (Maple Mini). /dev/cu... because I'm On Mac.

Why ftdi output doesn't work after ST-Link upload?

Never mind, I'll use "Generic STM32F1 series" from "STM32 Cores by STMicroelectronics" which works fine.