My STM32F767ZI-Neucleo-144 board is not supported by the online IDE.

I am trying to upload to my STM32F767ZI-Neucleo-144 board using the Arduino on-line IDE but each time I try I get this error message.

"
[COM7] -> [COM7]

[COM7] -> [COM7]

[COM7]

Wait for the port to reappear

[COM7] -> [COM7]

timeout

Flashing with command:C:/Users/admin/.arduino-create/arduino/bossac/1.7.0-arduino3/bossac.exe -i -d --port=COM7 -I -U true -i -e -w C:/Users/admin/AppData/Local/Temp/arduino-create-agent063665238/sketch_neuclio_144_blink.bin -R

Set binary mode

No device found on COM7

Send auto-baud

Set binary mode
"

The st-link driver detects the board on the device manager window and the IDE seems to detect the board alright. My board is selected as "Arduino MKR Vidor 4000" as my book tells me the none online Arduino 1.8.8 IDE or later had this sub menu "Neucleo-144" under "STM32 Boards (selected from submenu)" branch. I want to stay with the online IDE because it is more stable. Am I doing something wrong?

My source code "

/*
Blink

Turns an LED on for one second, then off for one second, repeatedly.

Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO
it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN is set to
the correct LED pin independent of which board is used.
If you want to know what pin the on-board LED is connected to on your Arduino
model, check the Technical Specs of your board at:

modified 8 May 2014
by Scott Fitzgerald
modified 2 Sep 2016
by Arturo Guadalupi
modified 8 Sep 2016
by Colby Newman

This example code is in the public domain.

*/

// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin LED_BUILTIN as an output.
pinMode(LED_BUILTIN, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (HIGH is the voltage level)
delay(2000); // wait for a second
digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
delay(500); // wait for a second
}

"

Thankyou for prompt answer,
From S. Korea.
YW Kim,