Problem

in visual you have a button "source/pivot language" which toggles the left side between source or pivot language. This button is always shown, even for tasks which do not use pivot language at all.

When you click on it, the source will disappear and you will see "an empty" page, or to be correct: a page with no text. The places of segments are present and even segment-based annotations are shown.

See screenshot:

Solution

The "source/pivot language" button should only be shown for tasks that have a pivot language. For those task which do not have pivot language, it simply makes no sense.