That option was there due to Firefox bug that got resolved in the meantime. So I removed it.
However this should not affect the URL (I mean, it can, but you should be able to fix it easily).
Just make sure your homepage URL ends with "/dial.html". If the URL matches the add-on URL exactly, it should be automatically cleared. You can get the correct URL from the Options page / first tab / first line.
If this didn't help, please let me know to my support e-mail.