Why do Sections create duplicated classes after pasting?

If you paste Sections from the same collection (for example everything from Evermind), you usually won’t get duplicated classes.

Duplicates appear when:

• you mix Sections from many different template collections,
• or you paste Sections into an existing project with its own class structure.
  

Using the XSync Chrome extension drastically reduces duplicated classes by intelligently mapping similar classes during pasting.