I recently found out about the txtHistoryBack parameter which prevents PostFinance to call the history.back() JavaScript function and avoids having to change the form action in checkout_confirmation.php from POST to GET.

I've uploaded an updated version of the postfinance.php file that adds txtHistoryBack set to false. Please use the language files from older versions of this contribution.

Just upload all new files and install it in your store's admin section. To get the URLs right that have to be sent to PostFinance, please refer to ASULIS' readme file, but don't forget to NOT tweak the checkkout_confirmation.php file as suggested. It is no longer necessary and by the way incompatible with other payment modules!

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