Reproduced with Chrome version 28.0.1500.52.

Repro steps:

1. Create a page.
2. Start a bullet list.
3. Copy and paste multiple lines of plain text in the line by the bullet.
4. Observe problem: All multiple lines are withing the same bullet point. By pressing enter in the middle of the text, a new line will be added with the right indexation but no bullet.

This happens only with Chrome. It works fine on Firefox and IE.