I’ve found a very strange behavior of a HTML table, where the width allocation of the cells depends on the count of rows. If I have 2 rows the cells have all the same width but when I insert another row the first column expands a little and the second column is narrower than the others.
I have uploaded an example on fiddle.
You can see this behavior when you delete the comment around the third row in the HTML.
Where does this behavior come from?
Table cells will expand to the content unless they have a fixed width. In your example you have table inside tables. Tables tend to have default values such as padding and cell spacing.
To get around this you can use a reset style sheet and modify the CSS of the table and its cells to your choosing
You may need to also perform CSS declarations such as collapsing borders if you really want it to be pixel perfect.