Currently, Microsoft Edge generates HAR files with a malformed HTTP version string, e.g.
"httpVersion": "HTTPS"
When Fiddler's HAR Import feature attempts to parse this data, it fails and this results in omitting *all* of the headers from display.
To mitigate this, Fiddler should look at the httpVersion string and if it lacks a slash, it should either add the slash (if this is enough to placate the response parser) or it should generate a dummy value for the entire token (e.g. "http/0.0") so that the rest of the header values are parsed correctly.
(I have filed a bug against Edge too).
Another failing test case is when the response headers are missing. Fiddler should at least show the status code and text.
{"log": {
"version": "1.2",
"creator": {
"name": "F12 Developer Tools",
"version": ""
},
"entries": [
{
"startedDateTime": "2018-08-27T19:10:17.899Z",
"time": 0,
"request": {
"method": "GET",
"url": "https://downloads.mailchimp.com/css/signup-forms/popup/1.0/common.css",
"httpVersion": "HTTPS/1.1",
"cookies": [],
"headers": [
{
"name": "Host",
"value": "downloads.mailchimp.com"
}
],
"queryString": [],
"headersSize": 85,
"bodySize": -1
},
"response": {
"status": 200,
"statusText": "OK",
"httpVersion": "HTTPS/1.1",
"cookies": [],
"headers": [],
"content": {
"size": 0,
"mimeType": "",
"text": ""
},
"redirectURL": "",
"headersSize": -1,
"bodySize": 0
},
"cache": {},
"timings": {
"blocked": -1,
"dns": -1,
"connect": -1,
"send": 0,
"wait": 0,
"receive": 0,
"ssl": -1
}
}
]
}
}