When rendering a link to a page in another space, the space key is not stripped from the page title. Since spacekeys are intended primarily for internal use, they can be safely stripped in this instance.

[DOC:Home] is currently rendered as DOC:Home but should be rendered as Home instead.

To replicate:

1) Install the Demo space
2) Create a new space
3) Edit the new space homepage and add a link [DS:Home]

If the space key is to be kept, it would be preferable to use the space name instead of the space key, eg have the link [DOC:Home] become Home (Documentation space).