I believe the correct behavior should be:
Second click on a URI that pays to address 'A' should remove the previous entry for A and add a new entry.
E.g. click on "Pay 2 BTC to XYZ", then click on "Pay 1 BTC to XYZ", the Send Coins should show the last one.
Click on "Pay 2 to XYZ", then click on "Pay 1 to VWX", Send Coins should show both recipients.
I believe the correct behavior should be:
Second click on a URI that pays to address 'A' should remove the previous entry for A and add a new entry.
E.g. click on "Pay 2 BTC to XYZ", then click on "Pay 1 BTC to XYZ", the Send Coins should show the last one.
Click on "Pay 2 to XYZ", then click on "Pay 1 to VWX", Send Coins should show both recipients.