Jetpack comments seems to have some sort of issue with some themes and the iframe. The basic iframe height is 315px. by default when the Jetpack comments are closed, there is a large space under it, which then fills some what when you click inside and it opens up.
I've tested this with the default theme for WordPress with only jetpack installed and there is a space. I've only been able to find two themes unedited where this isn't a problem.
I'm fully updated with both wordpress and jetpack. I've posted this on a number of forums and support groups and have yet in about 3 weeks now gotten a reply and only found one other person who was asking about the height being so large with jetpack comments. So clearly I'm not the only one.
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