When using the Python interpreter it frequently happens that the cursor jumps back to the start of the paragraph, erasing the last typed characters. So far this is only happening when making or modifying comments and lists, which means typing # and . It doesn't happen always, but very often.
When typing quickly this can remove a large piece of lastly typed code.
This started happening after the update to Zeppelin 0.7.3.
I added a video demonstrating the issue. Skip to 26 seconds in, it took a few tries to trigger this time.