@skyvan Are you using the Arduino 1.8.13? If so do you have a reference on how to use the ST Link to program the Blue Pill? I plan on trying again.
I use 1.8.14 built from the GIT repository.
Outside of the Arduino IDE I currently use st-flash to upload to the stm32f103 .
I built this from 'github' https://github.com/stlink-org/stlink. Once built
this can be used to flash the Arduino bootloader with one of Roger Clarks's
set of bootloaders available from https://github.com/rogerclarkmelbourne/STM32duino-bootloader.
The STM32 is connected to the Blue Pill's 4 pins on the end of the board. On the side of the st-link is a diagram indicating the pin use of the 10 pins. You only need to connect the 4 that match the 4 pins on the Blue Pill.
From within the bootloader_only_binaries directory, the basic command is
st-flash write generic_boot20_pc13.bin 0x08000000 (use whichever boot image applies to your Blue Pill).
Of course the you will need to move the Boot0 jumper to position 1 and press reset before this command. Once the bootloader is uploaded then you can swap the Boot0 jumper back to position 0.
If you have errors when trying to upload then you may need to upgrade the st-link firmware. See
Once you have installed the boot loader you will need to use the boards manager to install the ST boards into the Arduino IDE. You can get these from
http://dan.drown.org/stm32duino/package_STM32duino_index.json . The internet is littered with instructions on how to do this as a general process.
Basically then done. Restart the IDE, under tool select the STM32f103C series and selectas upload method STM32duino bootloader. Be aware - you could use the st-link to but this would wipe out your boot loader and you would not have direct access to Serial!
I have found the most critical part of the sketch upload is the timing between pressing the reset button and pressing upload. This will require a bit of trial and error.