Got d1-mini clones and not able to flash them

The following makes it work

esptool.py --port /dev/tty.wchusbserialfd12240  write_flash -fs 4MB-c1 -fm dio 0x0 espruino_2v04_esp8266_4mb_combined_4096.bin

As I suspected in the http://forum.espruino.com/comments/15179132 it meant that the firmware was actually fine. Just connecting to it has to have the XON/XOFF flow control turned off. I did not even realize something like this was even added and turned on by-default.

So the following allows me to connect:

espruino --config SERIAL_FLOW_CONTROL=false --no-ble -b 115200

Thanks for all your hints @MaBe