Adding columns to the correct location

The add columns function is not behaving properly

1. Select a table
2. Select a column (place the cursor inside it)
3. Click the "add a column before" button
4. The column is not added before the one seleted (in this instance it was created at the very start of the table)
5. Repeat step 2
6. Click the "add a column after" button
7. The column is not added after the column selected (in this instance is was created before the one selected)
8. Click the undo button. The last column is removed, but the first column remains (in edit mode)
9. Save and view the page. The colums are removed, but in edit mode, the first column inserted remains