esp 8266 issue "Leaving... Hard resetting via RTS pin..."

I'm new in arduino and esp8266 i trued to upload a simple blink example of esp

/*
  ESP8266 Blink by Simon Peter
  Blink the blue LED on the ESP-01 module
  This example code is in the public domain

  The blue LED on the ESP-01 module is connected to GPIO1
  (which is also the TXD pin; so we cannot use Serial.print() at the same time)

  Note that this sketch uses LED_BUILTIN to find the pin with the internal LED
*/

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);     // Initialize the LED_BUILTIN pin as an output
}

// the loop function runs over and over again forever
void loop() {
  digitalWrite(LED_BUILTIN, LOW);   // Turn the LED on (Note that LOW is the voltage level
  // but actually the LED is on; this is because
  // it is active low on the ESP-01)
  delay(1000);                      // Wait for a second
  digitalWrite(LED_BUILTIN, HIGH);  // Turn the LED off by making the voltage HIGH
  delay(2000);                      // Wait for two seconds (to demonstrate the active low LED)
}  

it's start well and the led start blinking and after a second it's stop and i get

Error downloading http://arduino.esp8266.com/versions/2.4.1/package_esp8266com_index.json
Sketch uses 257696 bytes (24%) of program storage space. Maximum is 1044464 bytes.
Global variables use 26572 bytes (32%) of dynamic memory, leaving 55348 bytes for local variables. Maximum is 81920 bytes.
esptool.py v2.6
2.6
esptool.py v2.6
Serial port COM4
Connecting....
Chip is ESP8266EX
Features: WiFi
MAC: 84:0d:8e:a4:77:12
Uploading stub...
Running stub...
Stub running...
Configuring flash size...
Auto-detected Flash size: 4MB
Compressed 261856 bytes to 191268...

Writing at 0x00000000... (8 %)
Writing at 0x00004000... (16 %)
Writing at 0x00008000... (25 %)
Writing at 0x0000c000... (33 %)
Writing at 0x00010000... (41 %)
Writing at 0x00014000... (50 %)
Writing at 0x00018000... (58 %)
Writing at 0x0001c000... (66 %)
Writing at 0x00020000... (75 %)
Writing at 0x00024000... (83 %)
Writing at 0x00028000... (91 %)
Writing at 0x0002c000... (100 %)
Wrote 261856 bytes (191268 compressed) at 0x00000000 in 17.0 seconds (effective 123.2 kbit/s)...
Hash of data verified.

Leaving...
Hard resetting via RTS pin...

how i can make it run for ever until i stop the ide note : after i run it again this line

Error downloading http://arduino.esp8266.com/versions/2.4.1/package_esp8266com_index.json disappear

I'm not sure if this related to newer versions of the Arduino IDE or something else, but if you power cycle the board after you see this message it will run as you expect.

I've also noticed that in my case (macOS Catalina) I also have to reset the board to be able to upload sketches.

Hope that helps.