Wiki language setting is not kept anymore after switching the language

STEPS TO REPRODUCE

1. Unzip a fresh XWiki instance
2. Set the wiki to be multilingual, with Supported Languages: EN, FR and default language EN
3. Go to Home page
4. Change the language to FR from Drawer > Languages
5. Click on Sandbox or other page, navigate through the wiki

EXPECTED RESULTS

The pages that have FR translation are displayed; the wiki UI is displayed in FR.

ACTUAL RESULTS

After changing the language to FR and navigate to other page (e.g. Sandbox), the wiki language changes back to EN.