Using the default settings and enabling window previews on hover, the feature works perfectly if only one window of a particular application is opened. However, when multiple windows of the same application is open, the window preview only shows an icon. I tested the window preview function with a plasma panel task manager and that work normally, so I think this problem has something to do with Latte Dock. Please refer to the image attached.
Created attachment 114779 [details] No preview when two windows are opened
Created attachment 114780 [details] Works normally with one window open
*** This bug has been marked as a duplicate of bug 397193 ***
Has been fixed in upcoming v0.8.1 and master branch...