Container Webview doesn't load on Firefox Desktop

[GeorgeWL]

Describe the bug

Seems to affect all frontend apps, the webview panel of the app doesn't load the preview, only showing the lightning symbol

Link to the blitz that caused the error

https://stackblitz.com/edit/vitejs-vite-51rwbg?file=index.html&terminal=dev

Steps to reproduce

1. Go to Dashboard
2. Create a new Frontend Project
3. Enter the project
4. See that webview does not load on Firefox

Expected behavior

Webview does load on Firefox

Parity with Local

• [X] I have run the project in my local machine and I could not reproduce the issue.

Screenshots

(work PC so covered up some internal-use only bookmarks)

Platform

Browser name  = Firefox
Full version  = 125.0
Major version = 125
navigator.appName = Netscape
navigator.userAgent = Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:125.0) Gecko/20100101 Firefox/125.0
performance.memory = undefined
Hash = 34455753

Additional context

console-export-2024-5-3_15-10-2.txt export of console.log

[GeorgeWL]

I also tried disabling uBlock on the site, this made no difference.

I am connected to the work network via a VPN, unsure if that will effect anything?

[GeorgeWL]

Just checked the same page at home, seems to be a issue with the work VPN specifically? Still, should probably show an error notification, rather than just a thunderbolt symbol

[kirjavascript]

hi 👋 thanks for reporting this issue!

Yeah, this is likely an issue with the VPN

Could you try and use curl -v https://foobar.w-credentialless-staticblitz.com/iframe.7dbe22a9.html to check if you correctly have access to the resources you need via the work VPN? If it fails we know it's that for sure.

It would be ideal to show a better message in this case, and we have plans to improve on this in future.

[GeorgeWL]

curl -v https://foobar.w-credentialless-staticblitz.com/iframe.7dbe22a9.html

I've tried that now, seeing a 200 status, I'll put the message here in a <details>

cURL response

Trying 172.67.187.137:443...
* Connected to foobar.w-credentialless-staticblitz.com (172.67.187.137) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*  CAfile: C:/Program Files/Git/mingw64/ssl/certs/ca-bundle.crt
*  CApath: none
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
* TLSv1.3 (IN), TLS handshake, Certificate (11):
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
* TLSv1.3 (IN), TLS handshake, Finished (20):
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.3 (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
* ALPN, server accepted to use h2
* Server certificate:
*  subject: CN=w-credentialless-staticblitz.com
*  start date: Apr 13 01:23:06 2024 GMT
*  expire date: Jul 12 01:23:05 2024 GMT
*  subjectAltName: host "foobar.w-credentialless-staticblitz.com" matched cert's "*.w-credentialless-staticblitz.com"
*  issuer: C=US; O=Google Trust Services LLC; CN=GTS CA 1P5
*  SSL certificate verify ok.
* Using HTTP2, server supports multiplexing
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* Using Stream ID: 1 (easy handle 0x23a567d1980)
> GET /iframe.7dbe22a9.html HTTP/2
> Host: foobar.w-credentialless-staticblitz.com
> user-agent: curl/7.78.0
> accept: */*
>
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* old SSL session ID is stale, removing
< HTTP/2 200
< date: Wed, 15 May 2024 11:25:15 GMT
< content-type: text/html; charset=utf-8
< last-modified: Wed, 27 Mar 2024 09:34:02 GMT
< x-amz-server-side-encryption: AES256
< cache-control: public, max-age=31557600
< accept-ranges: bytes
< x-cache: Miss from cloudfront
< via: 1.1 a332ecb068a370997b5e7bc811ff54ea.cloudfront.net (CloudFront)
< x-amz-cf-pop: LHR62-C5
< alt-svc: h3=":443"; ma=86400
< x-amz-cf-id: bTVq9Hntm2f_sFj1smabeB7zXbW0ACkxmqZ1rFk3-0l09WjAK9m7vg==
< cross-origin-embedder-policy: credentialless
< cross-origin-opener-policy: same-origin
< cross-origin-resource-policy: cross-origin
< vary: Origin, Accept-Encoding
< cf-cache-status: DYNAMIC
< report-to: {"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v4?s=gMYHXfj%2FjyPNSERFQ6QtXlYttLIReYjD%2BQw9tS2nkyrcda1XrLWNTSzyl%2BqsqnWw7TLEF5n5JRAZCXq8o3dyhIG9TCi1Piawub17CBfSLEL2BirsTRxLQhytZw37rQybCb5K1A5sQa3Bt0OOTVRxrhj1QRXwZJQo6mY%3D"}],"group":"cf-nel","max_age":604800}
< nel: {"success_fraction":0,"report_to":"cf-nel","max_age":604800}
< origin-agent-cluster: ?1
< server: cloudflare
< cf-ray: 8842c42609e39527-LHR
<
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<script src="iframe.main.7dbe22a9.js"></script>
</head>
<body></body>
</html>* Connection #0 to host foobar.w-credentialless-staticblitz.com left intact

[GeorgeWL]

not sure what's changed, but now it loads in fine

[kirjavascript]

fantastic! I'll close this issue then. feel free to open another if there are any other issues!