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I have created a very simple webview based Chrome app - it is almost identical to Google's create a simple kiosk app by using a text editor but even simpler in that it does not have the reset, or any other, button just my Web page content.

This works great in most normal kiosk situations supplied by policy or manually, however in the live environment I need to deploy this app I am behind a very restrictive firewall and Internet access is only available using a HTTP proxy (Squid). In this situation the webview content never shows up and the app appears to get stuck at the initializing stage.

I have access to the proxy logs and can see that webview's content is never being requested using the proxy - other HTTPS requests to Google's servers appear to be working normally and fine. Deploying a network sniffer allows me to see the webview content is being attempted by direct request which the firewall is dropping.

My desired config is to have the proxy configured under CrOS using the automatic mechanism http://wpad/wpad.dat but I have tried configuring manually, supplying this config by managed policy, as well as locally, in all possible combinations and my results all seem the same; webview in a kiosk app appears to ignore the system configured proxy.

If the kiosk_enabled app is used out of kiosk mode in the restricted environment it appears that the webview picks up the proxy settings of the signed on user correctly. It is only when in a proper kiosk mode that the proxy setting appears to be ignored by the webview.

My research would seem to suggest that a webview cannot have its proxy manually configured by API, although there does seem to be a Chromium issue (172285) requesting this; and other kiosk apps exhibit the same issue in my restricted environment, including Google's own Sign Builder app. So maybe what I'm trying to do just isn't possible (a bug?) although I have found no documentation to suggest this. I am really hoping there is some workaround that can make webview work with the system proxy setting and that someone reading this knows and is willing to share it.

I have successfully implemented my own hacky workaround, given that I have full control of the proxy if not the firewall, which sets up a reverse proxy config for the site my kiosk app's webview accesses, and thus it appears no proxy is needed for the webview as it looks like the site is local to the firewalled LAN. This is not a very generic solution though and I'm sure there will be others who do not have this option.

Thanks in advance for any advice or feedback,
Cheers
/dan

DanSut
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    Maybe you'll have to write a [native messaging](https://developer.chrome.com/extensions/messaging#native-messaging) helper that will redirect the requests. – wOxxOm Sep 14 '15 at 17:29
  • @wOxxOm that does look interesting and maybe a possibility, but the fact this app (and others like it) work when signed in, and out of full kiosk mode, suggest that the webview is able to use a proxy without doing anything _clever_. I'll edit the Q to add this potentially useful information. – DanSut Sep 14 '15 at 18:21
  • Dan, I realize this issue is quite old. I think I am having this same issue now. Did you ever find a solution? – tlaughlin Feb 05 '19 at 19:38
  • The Chromium bug mentioned in my Q is still open so I'm guessing this odd behavior still exists, but my workaround of making the kiosk Web app look like it was on the local network using a reverse proxy has worked perfectly fine for my needs ever since the time of this post so I have had neither the time or drive to find any other way of fixing this. – DanSut Feb 05 '19 at 22:46

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