Edit existing component / bug

I was trying to edit an existing component when I found this bug:
Component part number is Raspberry Pi B+ GPIO Male Shrouded Header
When I try to edit a pin label, the new label overlays the old label, and the label on pin one disappears.
Sometimes the new label is applied elsewhere.
I tried with different components, easy to reproduce.
Steps:

  1. on the schematics page, double click a component
  2. In the dialog displayed, click the “edit manually” (top, centre)
  3. On the Component Editor page, click “pins” on the right side panel.
  4. Click on the “edit” button, just under “pins”
  5. Change any pin name and save

I am new to Upverter, perhaps I am doing something wrong…?