Portal does not deliver users's localization in context of auto login if locale.prepend.friendly.url.style=2

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.0.X, Master
• Fix Version/s: 7.0.0 DXP FP40, 7.0.0 DXP SP7, 7.0.5 CE GA6, 7.0.X, 7.1.0 M1, 7.1.X, Master
• Component/s: Portal Services, Portal Services > Localization
• Labels:
  • ee-ts
  • liferay-digital-enterprise-70-sp7
  • liferay-fixpack-de-40-7010
• Branch Version/s:
  7.0.x
• Backported to Branch:
  Committed
• Story Points: 4
• Fix Priority: 2
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/54781

Behaviour description:
portal-ext.properties: locale.prepend.friendly.url.style=2

Preparation:

1. Ensure default language of Portal is "English (United States)"
2. Login as User "test"
3. Create new page "login"
4. Put "Sign in" Portlet onto this page
5. Go to Account Settings of Test-User
6. Change Language to: "Deutsch (Deutschland)"

Preparation for auto-login:

1. Put file "com.liferay.portal.security.auto.login.basic.auth.header.module.configuration.BasicAuthHeaderAutoLoginConfiguration.cfg" with content "enabled=true" to osgi/configs.
2. Set authentication type to Screen Name
3. Route your browser through debugging proxy "Burp Suite" to inject basic auth header.
4. Configure basic auth header inside burp:
   1. Go to Proxy > Options > Match and Replace, press "Add"
   2. Type: Request Header
      Match: [leave empty to add a new request header]
      Replace: Authorization: Basic dGVzdDp0ZXN0
   3. Press "Ok"

Test case 1:

1. Open Incognito-Session
2. Go to /login page
3. Portal redirects to /en/login (test-user is logged in) - this is invalid

Test case 2 - which nearer to our production scenario needs a new page "restricted" which has no VIEW permission for Guest.

1. Open Incognito-Session
2. Go to /restricted page
3. Portal redirects to /en/restricted (test-user is logged in) - this is invalid

According to my analysis at production, the redirect to "en/restricted" is done in the first place - before the login is done.
Our clear expectation is, that the portal delivers the german page according to the language preferences of the user.