We managed to support Windows XP in Slimjet 11 with significant efforts invested. However, based on the way the Chrome team has been quickly introducing more and more XP-incompatible code into the Chromium code base, it doesn’t make sense for us to spend a lot of time every time to find every little changes and undo them in order to support XP. Therefore, we have decided to stop supporting XP when we migrate to Slimjet 12 running on Chromium 52.
XP users can continue to download Slimjet 11 from the early version archive. If there is a critical security issue with Slimjet 11, we will update it into the Slimjet 11 branch.
As for Vista support, based on the current estimate, supporting Vista takes much less effort. However, I guess much fewer people use Vista anyway.
Thanks a lot for your understanding and support.