I got the basics of it working just fine using the Arduino IDE, but I decided to I wanted a more powerful editor, so I moved over to using Visual Studio Code. It works fine, the sketch opens, compiles, and uploads to the board with no issues. VS Code is a vastly better editor than the Arduino IDE could ever be.
Except VS Code flags 2 identifiers as unknown.
Firstly the U8G2_SSD1306_128X32_UNIVISION_F_HW_I2C for the display, and also D7 as a pin definition. In both cases I can mouse over the identifier, press F12, and it will correctly show me the definition from the appropriate header file. (Oddly, for the D7 definition in pins_arduino.h it also marks uint8_t as undefined but will also show its definition when I press F12)
As I said, despite this the sketch compiles, uploads, and runs just fine. I could ignore the error, but my OCD won't let me.
I have the Arduino for Visual Studio Code from Microsoft v0.2.29 (latest version) extension installed, and ESP8266 Community board definitions v2.6.3 installed. I'm using the U8g2 library by Oliver, v 2.27.6.
Anyone got any ideas on this?