Created attachment 60568 [details] Test case MathML 3 specify center as the default value of the columnalign attribute, instead of left. See test case.
Created attachment 60569 [details] Patch Patch fixing this bug
Comment on attachment 60569 [details] Patch This looks reasonable, but I know nothing about MathML. One suggestion for a slight improvement: you could link to the spec. :)
Here is the MathML 3 Draft part concerning mtable and columalign: http://www.w3.org/TR/MathML3/chapter3.html#presm.mtable
Comment on attachment 60569 [details] Patch Clearing flags on attachment: 60569 Committed r62945: <http://trac.webkit.org/changeset/62945>
All reviewed patches have been landed. Closing bug.