This library initializes the ArduinoOTA library in combination with the SSD1306 (SSD1306Wire) library to display the OTA flash process.
Clone the project and include the header file with
#include <OTAsetupSSD1306.h>
The main part of this code was written by ThingPulse in the esp8266-oled-ssd1306 library.
Also the OTA introduction at lastminuteengineers was helpful.