Hi all,
With the move to a more Ajax-based UI in 1.4 and the completion of that step in 1.5 (full ajax form submission), we now need support for the _javascript_ FormData object. All modern browsers support it; some for a long time already:
http://caniuse.com/#search=formdata .
However, IE8 and 9 don't. Microsoft has declared IE8 and IE9 to be unsupported on their desktop operating systems (
https://support.microsoft.com/en-us/lifecycle#gp/Microsoft-Internet-Explorer) and the project has declared IE versions up to 7 as unsupported before due to lacking standards implementations (for those versions: incorrect implementation of the behaviour of the BUTTON tag).
We think it's acceptable to drop these older browsers because there are several workarounds:
a. Upgrade IE on your desktop to 10 or 11
b. Install FireFox
c. Install Chrome
d. Install Safari
e. Install Opera
Additionally, StatsCounter shows per end of 2015 only IE11 with a market share worth mentioning (
http://gs.statcounter.com/#all-browser_version-ww-monthly-201510-201512-bar) and wikipedia lists IE9 not supporting TLS1.1 and TLS1.2 (
https://en.wikipedia.org/wiki/Transport_Layer_Security#Web_browsers) which is now a PCI compliance requirement in the US (that is, making a payment to a webshop -- meaning that everybody who uses webshopping should be moving away from IE8 and 9 anyway).