All major internet browsers (e.g. Chrome, Internet Explorer, Firefox) are changing the way that they validate website security certificates to ensure the highest security level for users when making payments. As a result of this change, you may see security warnings (e.g. browser errors, security certificate warnings) on your web browser when using a secure website. This will only happen if the website you are visiting is using an older security certificate.
To address this issue, most sites are updating web certificates for all payment pages and forms. This change will not impact the majority of online shoppers apart from a small fraction who are using very outdated browsers on old computers. These shoppers will not be able to transact on any payment processing or online banking facility which has made these industry-wide changes.
It is always recommended to use a current version of your browser as it will ensure operation with web sites using current technology and also most importantly have the latest security fixes and patches.