1.4.7 Beta 1
Pre-releaseCryptography change: The previous AES encryption routines have been replaced with a newer approach based on the WebCrypto API. I've been forced into this change earlier than expected but there should be no notable change to the security of the communication between KeePass and Firefox, merely an implementation change. In fact, the functionality I am now using has only been available to Firefox addons for 2 weeks so this is very cutting edge stuff, hence why I want to call it out specifically to all technical followers and beta testers. I don't intend to announce this implementation change to all users, but I will note the impact on performance as per below. On the off-chance that I find enough time I might post about some of the technical details merely as an interesting guide for other developers - please shout if you're interested in that.
You can see the exact code changes in PR #362 - feel free to comment in there or in the associated issue #356
Performance change: Some complex changes to Firefox over the recent versions leading up to Firefox 37 will cause some aspects of KeeFox version 1.4.6 and older to be much slower for users with large password databases and/or slow computers.
This new version speeds things up (now faster than ever before) but it will be slightly slower for users of Firefox 36 and below. I recommend upgrading since it is unlikely you will notice the slow down but if your specific situation does result in worse performance, please just remember to upgrade KeeFox before you upgrade to Firefox 37.
Firefox 37 is due for release on the 7th of April 2015 and is already available for download as the "Firefox Developer Edition".
There are more technical details about the change here: #356