Description

User interface translations might not be available after a user sets a new context language for the site. For example, EXM buttons, Content or Experience Editor labels, as well as the Desktop start menu items can be textless. The issue happens because the site is rendered in the context language that is parsed from the changed value in the "Accept-Language" header (via the "site#lang" cookie). As the current language has no available translations, the rendered labels disappear. When manually removing  the "site#lang" cookie and refreshing the page, all labels and translations are displayed correctly.

Solution

To resolve the issue:

1. Download and install the patch compatible with the affected product version found on this page:
   https://github.com/SitecoreSupport/Sitecore.Support.100371.100542/releases.
   To get a solution for another XP release, contact Sitecore Support.
2. Clean up cookies and the browser cache.