A few Issues on page /docs/04-metadata.html

The first paragraph mentions Figure 3:

* Can we add a link to the figure?
* Are we sure the text refers to Figure 3 or Figure 2.
* This chapter shows Figure 2 and another figure without caption. Can we add a caption and assign a number to the second figure?

In the paragraph before Figure 2, there is a link to Section 3. This link is incorrect and should now point to Section 5.