Please add the following CSS rule to your page:
.k-window-content > .km-scroll-container
The problem is caused by an additional <div class="km=scroll-container"> element, which is inserted between div.k-window-content and your table. This <div> ensures touch device scroll capabilities, but breaks the sequence of elements with an explicit height, so the table's percentage height is ignored.
Indeed, it would be nice if the additional <div> can check the height styles applied to its parent and child and assume a correct height accordingly, however, this is not possible in all cases (e.g. when using external CSS styles). What we will do is to add the above CSS rule in our base (common) stylesheet to support this particular case.
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