WebIde not compiling code at upload time if already connected except if reconnection at upload?

I have some errors when trying the example below on an original Espruino Rev 1.4b.

var c = E.compiledC(`
    // int sum(int, int)
    int sum(int len, unsigned char *data){
      int s = 0;
      while (len--)
        s += *(data++);
      return s;
    }
    `);
    var str  = E.toString("\1\2\3\4\5\6"); // create a flat string
    print(c.sum(str.length, E.getAddressOf(str,true)));

It goes well, see first and second logs below, if I disconnect from webide, then upload the very same example, reconnecting at the prompt from wedide (0.68.5) just before it uploads the source. There no need to disconnect physically the board.

No error or just warnings, and a correct result of 21.

Note that printing process.env.EXPORTS gave once a truncated string with no closing " and no ending } and no prompt for the next command until I press the Enter key on the left side of the WebIde. Then I get the rest of the strings, json closed and prompt. This is also true on the error case.
On the other hand, process.env sends a full JSON with everything apparently correct.

>
 _____                 _
|   __|___ ___ ___ _ _|_|___ ___
|   __|_ -| . |  _| | | |   | . |
|_____|___|  _|_| |___|_|_|_|___|
          |_| http://espruino.com
 1v95 Copyright 2017 G.Williams
>21
=undefined
>process.env.EXPORTS
={ "jsvLock": 131929, "jsvLockAgainSafe": 131915, "jsvUnLock": 131889, "jsvSkipName": 19429,
  "jsvMathsOp": 24927, "jsvMathsOpSkipNames": 24977, "jsvNewFromFloat": 132269, "jsvNewFromInteger": 132305, "jsvNewFromString": 133473,
  "jsvNewFromBool": 132289, "jsvGetFloat": 19713, "jsvGetInteger": 17081, "jsvGetBool": 20437, "jspeiFindInScopes": 31009,
  "jspReplaceWith": 31069, "jspeFunctionCall": 35349, "jspGetNamedVariable": 188129, "jspGetNamedField": 189697, "jspGetVarNamedField": 189293,
  "jsvNewWithFlags": 132085 }
> process.env
={
  "VERSION": "1v95",
  "BUILD_DATE": "Dec 15 2017",
  "BUILD_TIME": "17:07:34",
  "GIT_COMMIT": "7dbffcf5da09570bd95714b2386a12ab25ab1d50",
  "BOARD": "ESPRUINOBOARD",
  "CHIP": "STM32F103RCT6",
  "CHIP_FAMILY": "STM32F1",
  "FLASH": 262144, "RAM": 49152,
  "SERIAL": "34ffdb05-42573838-24631743",
  "CONSOLE": "USB",
  "EXPORTS": { "jsvLock": 131929, "jsvLockAgainSafe": 131915, "jsvUnLock": 131889, "jsvSkipName": 19429,
    "jsvMathsOp": 24927, "jsvMathsOpSkipNames": 24977, "jsvNewFromFloat": 132269, "jsvNewFromInteger": 132305, "jsvNewFromString": 133473,
    "jsvNewFromBool": 132289, "jsvGetFloat": 19713, "jsvGetInteger": 17081, "jsvGetBool": 20437, "jspeiFindInScopes": 31009,
    "jspReplaceWith": 31069, "jspeFunctionCall": 35349, "jspGetNamedVariable": 188129, "jspGetNamedField": 189697, "jspGetVarNamedField": 189293,
    "jsvNewWithFlags": 132085 }
 }
> 

Ide log corresponding:
```
ERROR: RECEIVE ERROR: {"connectionId":1,"error":"device_lost"}
Disconnect callback...
WARNING: [notify_warn] Disconnected

Disconnected
Connecting...
ForceThrottle option is set - set Slow Write = true
[object Object]
Connected [object Object]
Found a prompt... great!
Sending...
---> "\u0010console.log(\"<\",\"<<\",JSON.stringify(process.env),\">>\",\">\")\n"
Sent
Got "< << {\"VERSION\":\"1v95\",\"BUILD_DATE\":\"Dec 15 2017\",\"BUILD_TIME\":\"17:07:34\",\"GIT_COMMIT\":\"7dbffcf5da09570bd95714b2386a12ab25ab1d50\",\"BOARD\":\"ESPRUINOBOARD\",\"CHIP\":\"STM32F103RCT6\",\"CHIP_FAMILY\":\"STM32F1\",\"FLASH\":262144,\"RAM\":49152,\"SERIAL\":\"34ffdb05-42573838-24631743\",\"CONSOLE\":\"USB\",\"EXPORTS\":{\"jsvLock\":131929,\"jsvLockAgainSafe\":131915,\"jsvUnLock\":131889,\"jsvSkipName\":19429,\"jsvMathsOp\":24927,\"jsvMathsOpSkipNames\":24977,\"jsvNewFromFloat\":132269,\"jsvNewFromInteger\":132305,\"jsvNewFromString\":133473,\"jsvNewFromBool\":132289,\"jsvGetFloat\":19713,\"jsvGetInteger\":17081,\"jsvGetBool\":20437,\"jspeiFindInScopes\":31009,\"jspReplaceWith\":31069,\"jspeFunctionCall\":35349,\"jspGetNamedVariable\":188129,\"jspGetNamedField\":189697,\"jspGetVarNamedField\":189293,\"jsvNewWithFlags\":132085}} >> >\r\n"
Loading http://www.espruino.com/json/ESPRUINOBOARD.json
Searching for json/ESPRUINOBOARD.json
json/ESPRUINOBOARD.json found in offline archive
Board JSON loaded
Firmware >1.43 supports faster writes over USB
ForceThrottle option is set - set Slow Write = true
FIRMWARE: Current 1v95, Available 1v95
Device found (connectionId=2)
[success] Connected to port /dev/ttyACM0
Connected to port /dev/ttyACM0
WARNING: [notify_warn] Errors while minifying - sending unminified code.
Found a prompt... great!
Sending...
---> "\u0010reset();\n\u0010setTime(1518684180.54);\n\u0010var c = (function(){\u001b\n var bin=atob(\"ChgAIJFCA9AR+AE7GET553BHAAA=\");\u001b\n return {\u001b\n sum:E.nativeCall(1, \"int(int, int)\", bin),\u001b\n };\u001b\n})();\n\u0010var str = E.toString(\"\1\2\3\4\5\6\");\n\u0010print(c.sum(str.length, E.getAddressOf(str,true)));\n\n"
Splitting at "reset();\n", delay 250
ERROR: [notify_error] Input_0:8: ERROR