when using a -webkit-transition across the "zoom" property and only when increasing the zoom factor, elements inside a zoomed container which specify fixed widths seem to "snap" to their destination width/height in the first frame of the animation, zoom based on this laid out size, and upon the final frame, snap *back* to the first-frame final size. It's unclear if font sizes changing to be larger than the destination size is related. See attached test case. Also, wasn't sure if this should have been filed under "CSS", so apologies in advance if it's in the wrong component.
Created attachment 28719 [details] css zoom "snapping" bug demonstrates the bug for both images and other block elements.
It's actually a bug that transitions run when zoom changes (bug 24807).
*** This bug has been marked as a duplicate of bug 24807 ***