Undefined error in testreport

[Piri1972]

Hi,
After testing my site, I see there is an undefined error which is slowing down my site. The test results are:

URL: https://www.oostevaar.nl/undefined
Loaded By: https://www.oostevaar.nl/:0
Host: http://www.oostevaar.nl
IP: 185.37.70.27
Error/Status Code: 404
Priority: LOWEST
Protocol: HTTP/2
HTTP/2 Stream: 31, weight 147, depends on 29, EXCLUSIVE
Request ID: 5543.150
Client Port: 40650
Discovered: 1.172 s
Request Start: 1.173 s
Time to First Byte: 2147 ms
Content Download: 2 ms
Bytes In (downloaded): 7.7 KB
Uncompressed Size: 26.0 KB
Bytes Out (uploaded): 1.4 KB
{
"ip_addr": "185.37.70.27",
"full_url": "https://www.oostevaar.nl/undefined",
"initiator_line": 0,
"bytesOut": 1447,
"load_ms": 2149,
"http2_stream_id": 31,
"http2_stream_weight": 147,
"request_id": "5543.150",
"minify_total": null,
"chunks": [
{
"bytes": 7902,
"ts": 3321.923
}
],
"cacheControl": "no-cache, must-revalidate, max-age=0",
"score_compress": -1,
"id": "5543.150",
"dns_end": -1,
"priority": "LOWEST",
"http2_stream_exclusive": 1,
"image_total": null,
"minify_save": null,
"score_cookies": -1,
"ttfb_ms": 2147,
"score_cache": -1,
"connect_start": -1,
"score_cdn": -1,
"cache_time": null,
"objectSizeUncompressed": 26632,
"load_start": 1173,
"server_port": "443",
"protocol": "HTTP/2",
"score_gzip": -1,
"type": 3,
"method": "GET",
"ssl_end": -1,
"objectSize": 7902,
"gzip_total": null,
"contentType": "text/html",
"initial_priority": "Low",
"initiator_column": "",
"expires": "Wed, 11 Jan 1984 05:00:00 GMT",
"score_combine": -1,
"score_etags": -1,
"initiator_type": "parser",
"frame_id": "AC4A0605CA3CB748DCC1579044794D45",
"host": "www.oostevaar.nl",
"bytesIn": 7902,
"raw_id": "5543.150",
"gzip_save": null,
"score_keep-alive": -1,
"is_secure": 1,
"dns_start": -1,
"server_count": null,
"score_minify": -1,
"initiator": "https://www.oostevaar.nl/",
"connect_ms": -1,
"socket": 57,
"created": 1172,
"url": "/undefined",
"load_start_float": 1173.211,
"client_port": "40650",
"contentEncoding": "gzip",
"headers": {
"request": [
":path: /undefined",
"accept-language: en-US,en;q=0.9",
"accept-encoding: gzip, deflate, br",
"sec-fetch-site: same-origin",
"accept: image/webp,image/apng,image/*,*/*;q=0.8",
"user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.97 Safari/537.36 PTST/200604.150630",
":scheme: https",
"referer: https://www.oostevaar.nl/",
"sec-fetch-mode: no-cors",
":method: GET",
":authority: http://www.oostevaar.nl",
"sec-fetch-dest: image"
],
"response": [
"status: 404",
"content-length: 7902",
"content-encoding: gzip",
"expires: Wed, 11 Jan 1984 05:00:00 GMT",
"vary: Accept-Encoding",
"server: nginx",
"link: <https://www.oostevaar.nl/wp-json/>; rel=\"https://api.w.org/\"",
"cache-control: no-cache, must-revalidate, max-age=0",
"date: Thu, 11 Jun 2020 14:40:02 GMT",
"content-type: text/html; charset=UTF-8",
":status: 404"
]
},
"dns_ms": -1,
"connect_end": -1,
"server_rtt": null,
"responseCode": 404,
"ssl_ms": -1,
"http2_stream_dependency": 29,
"image_save": null,
"ssl_start": -1,
"cdn_provider": null,
"load_end": 3322,
"ttfb_start": 1173,
"ttfb_end": 3320,
"download_start": 3320,
"download_end": 3322,
"download_ms": 2,
"all_start": 1173,
"all_end": 3322,
"all_ms": 2149,
"index": 21,
"number": 22

What can cause this error??

[Cymru]

Did you figure this out? I am getting several of these while testing on Moto G4 and only one when testing on cable/Chrome. It appears to be the same type of thing and looking for an image. Be interested if you found anything. Thanks.