Card Payments error using Firefox

[#1]

I've just paid my Line Rental Saver using a credit card and discovered that a persistent problem that I first encountered joining PlusNet 3 years ago.
Using Firefox for card payments is next to impossible because of an error that occurs with the drop down boxes for card start and expiry dates .
In Firefox the drop down box for July for example is 7 In IE it is 07 .
In FF this means that the date is declared invalid and the transaction cannot proceed.
I raised this problem after trying to pay my initial charges on joining PlusNet in 2011 ........I can't believe it still persists. I remember it nearly put me off joining initially.

[#2]

Unfortunately I can't check as my LRS isn't due for renewal but I had no problem renewing using Firefox and my card also runs out in July

[#3]

Maybe it's just me? - if so have I got a setting wrong? - any ideas anyone?

[#4]

Have you got Trusteer monitoring installed? That caused me problems with Firefox, including when trying to access my bank account and they recommended it. I've had no problems since I removed it.

[#5]

nope - no trusteer installed.
I might add I only ever have this problem with drop downs on PlusNet - not on any other payment sites using Firefox

[#6]

I use Firefox (and have done for years) almost exclusively but have never had an issue with the drop downs.
I would try the LRS bit as a test but I don't want to renew mine this time around as I'm thinking of shuffling the packages around next year.

[#7]

I paid my LRS by credit card using Firefox on 9th Dec. No issues with the drop-down boxes.
I don’t have Trusteer on either. Only extension is NoScript.
Good luck finding the cause.

[#8]

I remember I managed to pay LRS one year using a card that had an expiry date of Oct,Nov or Dec - ie the two digits were present and the transaction proceeded OK -
Only fails if Expiry date is Jan- Sept when that initial zero is missing 

[#9]

I'll go see if I can find the status of this problem. Is it a specific version of firefox that exhibits this behaviour, or does it happen in any of them?

[#10]

Using  standard Firefox 34 currently  - no idea which other versions I was using over the years - always kept up to date though...........

[#11]

Hmm we don't seem to have an internal problem raised on this, I'm also struggling to replicate it. I've just gone to add a card and the dropdowns are showing 01,02,03 etc correctly. This is using Firefox version 32.

[#12]

Edit after succeeding post
Using FF34 I see a two digit number

[#13]

OK this is is a screenshot of what I get -- weird
.....this was for adding card to account - I cannot now get to LRS page as I have now paid it

[#14]

Try starting Firefox in safe mode and see if it is the same

[#15]

Good suggestion Oldjim, that should rule out any plugins causing this problem.