2M sketch Space

First, find the path of linkage description file. On Mac or Unix-like, it should be

[User home]/.platformio/packages/[frame work]/tools/sdk/ld

For default ESP8266 framework, it will be

~/.platformio/packages/framework-arduinoespressif8266/tools/sdk/ld

Copy eagle.flash.4m.ld to eagle.flash.4m2m.ld.

Modify the line

PROVIDE ( _SPIFFS_start = 0x40300000 );

to

PROVIDE ( _SPIFFS_start = 0x40400000 );

Save and done.