resize: vertical does not restrict to vertical resize This seems easy to fix. It could just effectively do max-width: current width. The example is taken from another bug I'm filing. But you should only be able to resize the div vertically.
Horizontal restriction is broken as well.
<rdar://problem/5682745>
*** Bug 19170 has been marked as a duplicate of this bug. ***
It's possible to workaround this bug in some circumstances by setting setting the max-width attribute. However, this doesn't work if you use %ages. Setting max-width to 100%, say, will cause the computed max-width to end up as none. I'm not sure if this is another bug or not.
Created attachment 31620 [details] Ignore movement along the non-resizing axis
Fixed in <http://trac.webkit.org/projects/webkit/changeset/44914>.