My ESP-12F does not work with 1v95 and latest master

I have this problem too with espruino_1v95_esp8266_4mb_combined_4096.bin.

I can flash the 4M image to my 4M NodeMCU, and reboot it as many times as I want, but as soon as I do a wifi.save() then reboot with require("ESP8266").reboot() then I get a serial console full of this over and over:

Fatal exception (3): 
epc1=0x401000b8, epc2=0x00000000, epc3=0x00000000, excvaddr=0x401000df, depc=0x00000000

The wifi data is stored at the end of flash, so I thought it may be the end of my 4M flash was faulty, however I've tried pretending the flash layout is 2M and 1M with:

esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash --flash_freq 40m --flash_mode qio --flash_size 2MB 0x0000 "boot_v1.6.bin" 0x1000 espruino_esp8266_user1.bin 0x1FC000 esp_init_data_default.bin 0x1FE000 blank.bin

esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash --flash_freq 40m --flash_mode qio --flash_size 1MB 0x0000 "boot_v1.6.bin" 0x1000 espruino_esp8266_user1.bin 0xFC000 esp_init_data_default.bin 0xFE000 blank.bin

and neither of these fixed the problem.

I have tried both the combined image and the indvidual images as above, neither worked.

I have tried the previous versions:

• espruino_1v94_esp8266_4mb_combined_4096.bin
  
• espruino_1v92_esp8266_4mb_combined_4096.bin
  
• espruino_1v93_esp8266_4mb_combined_4096.bin
  
  

and all of these worked fine.

So it seems there is some regression between 1v94 and 1v95 which breaks wifi save or load on ESP8266 4M.

It might be worth noting that both MicroPython's boot/main files and Arduino sketches work fine on my board, though as I understand they don't store anything at the end of flash.