Language setting is lost for new browser sessions

[m2martin]

Deployment Type

Self-hosted

NetBox Version

v4.0.6

Python Version

3.12

Steps to Reproduce

1. Be sure to have LOGIN_TIMEOUT > 0 set
2. Login with a user which has language set to auto
3. Netbox will show in the language determined from browser language
4. Go to user preferences and set an alternate language
5. Netbox will show in alternate language (django_language cookie is set)
6. Close your browser and navigate to your Netbox again with a new browser instance (of course with the same browser)
7. The user is still logged in but language is again detected by browser language

This is because django_language cookie's lifetime is set to browser session's lifetime. Each time the browser is closed, the cookie is deleted. Because no new login happens, the language is not set (related #16512).

Expected Behavior

The user's language setting is applied

Observed Behavior

Browser language is applied.