Saving a space template in source editor corrupts it

1. Create a space template.
2. Enter some plain text and create a list variable.
3. Save the template.
4. Create a page based on the template.
   New page looks good.
5. Edit the template.
6. Click [ <> ] (Open in source editor).
   Note that list values for your new variable are stored in a <ul> structure at the top of the document.
7. Click Apply.
   The <ul> containing the variable values is now visible in the template.

The same thing happened with a multiline text variable--the variable definition is displayed at the top of the document in the source editor, and clicking Apply makes it visible in the template body even though no changes were made.