Bugzilla

On desktop the issue also happens for `about:about`, `about:networking`, `about:debugger`, and those are just the ones I've tested. They end up being shown the `connectionFile` text instead of the `connectionInternal` case in `browser/components/controlcenter/content/panel.inc.xul`:
```
          <description when-connection="chrome">&identity.connectionInternal;</description>
          <description when-connection="file">&identity.connectionFile;</description>
```

So I'm guessing that's fine?



However on mobile the problem is that there is a whitelist that `about:compat` isn't in yet in `mobile/android/chrome/content/browser.js`:
```
    let whitelist = /^about:(about|accounts|addons|buildconfig|cache|config|crashes|devices|downloads|experiments|fennec|firefox|feedback|home|license|logins|logo|memory|mozilla|networking|privatebrowsing|rights|serviceworkers|support|telemetry|webrtc)($|\?)/i;
    if (uri.schemeIs("about") && whitelist.test(uri.spec)) {
        return this.IDENTITY_MODE_CHROMEUI;
    }
```

I'm making a test build right now to confirm if that's all it is.

On desktop the issue also happens for `about:about`, `about:networking`, `about:debugging`, and those are just the ones I've tested. They end up being shown the `connectionFile` text instead of the `connectionInternal` case in `browser/components/controlcenter/content/panel.inc.xul`:
```
          <description when-connection="chrome">&identity.connectionInternal;</description>
          <description when-connection="file">&identity.connectionFile;</description>
```

So I'm guessing that's fine?



However on mobile the problem is that there is a whitelist that `about:compat` isn't in yet in `mobile/android/chrome/content/browser.js`:
```
    let whitelist = /^about:(about|accounts|addons|buildconfig|cache|config|crashes|devices|downloads|experiments|fennec|firefox|feedback|home|license|logins|logo|memory|mozilla|networking|privatebrowsing|rights|serviceworkers|support|telemetry|webrtc)($|\?)/i;
    if (uri.schemeIs("about") && whitelist.test(uri.spec)) {
        return this.IDENTITY_MODE_CHROMEUI;
    }
```

I'm making a test build right now to confirm if that's all it is.