In Online Editor, if you change the vertical align property in a table cell (or a table header), there's no visual change in the editor. The table cells content seems to always be in the middle.
Steps to reproduce:
1. Create a blog post
2. Add table with at least 2 columns
3. In the first cell, put several paragraph
4. In the second cell, put a short content and set the valign to top (or bottom)
The content of the second cell is still vertically aligned in the middle.