Inserting a new row below modifies the PRIMARY selection

After I tell the editor to insert a new table row below, the PRIMARY selection is replaced as if everything from the beginning of the page were selected; the current PRIMARY selection is obliterated.

Steps to reproduce (requires windows)

1. Create a new page
2. Add some text "This is a test"
3. Select text
4. Add a table (3x3) using the editor add table feature
5. Insert my cursor into the table
6. Click the add row button on the editor toolbar and confirm that a new row is generated
7. Paste the previously copied text
8. Observe that the text that has been pasted is the same as that which i had previously copied