docs/esp8266/quickref: Add info about WebREPL.

docs/esp8266/quickref.rst

@@ -273,3 +273,32 @@ For low-level driving of a NeoPixel::
 
     import esp
     esp.neopixel_write(pin, grb_buf, is800khz)
+
+WebREPL (web browser interactive prompt)
+----------------------------------------
+
+WebREPL (REPL over WebSockets, accessible via a web browser) is an
+experimental feature available in ESP8266 port. Download web client
+from https://github.com/micropython/webrepl , and start daemon using::
+
+    import webrepl
+    webrepl.start()
+
+(Release version will have it started on boot by default.)
+
+On a first connection, you will be prompted to set password for future
+sessions to use.
+
+The supported way to use WebREPL is by connecting to ESP8266 access point,
+but the daemon is also started on STA interface if it is active, so if your
+routers is set up and works correctly, you may also use it while connecting
+to your normal Internet access point (use ESP8266 AP connection method if
+face any issues).
+
+WebREPL is an experimental feature and a work in progress, and has known
+issues. There's also provision to transfer (both upload and download)
+files over WebREPL connection, but it has unstable status (be ready to
+reboot a module in case of issues). It still may be a practical way to
+get script files onto ESP8266, so give it a try using ``webrepl_cli.py``
+from the repository above. See forum for other community-supported
+alternatives to transfer files to ESP8266.