Steps to reproduce:

1. Start with a page that contains a dead URL.
2. Copy a working URL that will replace the broken link.
3. Select the dead URL in the page.
4. Paste (Ctrl+V) the new URL into the selected text.

Expected result:
The selected URL (text) should have been replaced with the new URL (text) from the clipboard.

Actual result:
The URL in the clipboard was appended with the selected URL.