Websocket Closed on chrome but no on safari (proxy behind)

When I open a notebook on chrome the logs are:

```
[I 18:35:02.082 NotebookApp] Adapting to protocol v5.1 for kernel 28d14fb3-8ded-4024-b36a-598778c0bc1a
[D 18:35:02.083 NotebookApp] 101 GET /api/kernels/28d14fb3-8ded-4024-b36a-598778c0bc1a/channels?session_id=C3A7DF49C6E842D7A8A56A6F4958D9E5 (127.0.0.1) 4.41ms
[D 18:35:02.084 NotebookApp] Opening websocket /api/kernels/28d14fb3-8ded-4024-b36a-598778c0bc1a/channels
[D 18:35:02.084 NotebookApp] Connecting to: tcp://127.0.0.1:40835
[D 18:35:02.085 NotebookApp] Connecting to: tcp://127.0.0.1:52911
[D 18:35:02.086 NotebookApp] Connecting to: tcp://127.0.0.1:40293
[D 18:35:02.239 NotebookApp] activity on 28d14fb3-8ded-4024-b36a-598778c0bc1a: status
[D 18:35:02.242 NotebookApp] activity on 28d14fb3-8ded-4024-b36a-598778c0bc1a: status
[D 18:35:02.388 NotebookApp] Websocket closed 28d14fb3-8ded-4024-b36a-598778c0bc1a:C3A7DF49C6E842D7A8A56A6F4958D9E5
[D 18:35:04.257 NotebookApp] Initializing websocket connection /api/kernels/28d14fb3-8ded-4024-b36a-598778c0bc1a/channels
[I 18:35:04.260 NotebookApp] Adapting to protocol v5.1 for kernel 28d14fb3-8ded-4024-b36a-598778c0bc1a
[D 18:35:04.261 NotebookApp] 101 GET /api/kernels/28d14fb3-8ded-4024-b36a-598778c0bc1a/channels?session_id=C3A7DF49C6E842D7A8A56A6F4958D9E5 (127.0.0.1) 4.45ms
[D 18:35:04.261 NotebookApp] Opening websocket /api/kernels/28d14fb3-8ded-4024-b36a-598778c0bc1a/channels
[D 18:35:04.261 NotebookApp] Connecting to: tcp://127.0.0.1:40835
[D 18:35:04.262 NotebookApp] Connecting to: tcp://127.0.0.1:52911
[D 18:35:04.263 NotebookApp] Connecting to: tcp://127.0.0.1:40293
[D 18:35:04.418 NotebookApp] activity on 28d14fb3-8ded-4024-b36a-598778c0bc1a: status
[D 18:35:04.421 NotebookApp] activity on 28d14fb3-8ded-4024-b36a-598778c0bc1a: status
[D 18:35:04.564 NotebookApp] Websocket closed 28d14fb3-8ded-4024-b36a-598778c0bc1a:C3A7DF49C6E842D7A8A56A6F4958D9E5
```

But when I connect with safari everything works.

I am behind a proxy and I have no idea why it is working on safari but not on chrome. I tried on incognito mode as well.

Start by reproducing the notebook websocket failure in Chrome while the notebook is behind a proxy, comparing the supplied Chrome logs with Safari behavior. Inspect the proxy and browser websocket diagnostics; the issue is done when the kernel channel remains connected and Chrome can use the notebook normally.

Written by the indexing model from the issue text.