eclipse many little boxes under the main window

I am using eclipse neon for Java development. At the bottom of the eclipse window there should be one little box with 5 yellow icons/buttons in it: "Restore welcome", "Overview", "Tutorials", "Samples", and "What's new".

The problem is, I have 40 of them. They appear one after the other, now in 4 rows at the bottom of the IDE. See below.

How can I trim them down to one?

Solution

This seems a bug in older neon version on Linux and it already got resolved. Please download the latest available neon version and check.