The last Webkit Nightly version on which I can confirm everything is working is 179347. While I've not tried all of the subsequent releases, I have tried 179393, 179398, 179435, 179466, 179515, 179701, 179750, & 179776. I've experienced what I believe to be the same issue when conducting two separate actions on eBay. If one clicks on the "Ask a question" link at the bottom of any auction listing, one is directed to a "Find answers from ..." dialogue. If one clicks on the radio button before any of the answer categories a second dialogue appears which inquires if "Did we answer your questions?". In Safari 7.1.3 and Webkit Nightly 179347 this "Did we answer your questions?" still appears. In all the subsequent Nightly versions I listed above, it does not. As an example, here's a link to the "Find answers" page for an eBay auction which doesn't expire until Mar. 1st: http://goo.gl/yhKN7b. The second occurrence requires one to login to one's eBay account and view the "Messages" dialogue. Normally to view a message one clicks on the message and it appears below. Again, in Safari 7.1.3 and Webkit Nightly 179347 this works. In the subsequent Nightly versions listed above it does not. Since the second occurrence requires logging into an eBay account to view one's messages, I'm not offering an example. I have also tried irefoxDeveloperEdition 37.0a2 and Chromium 38.0.2125.0. Neither have content visibility issues.
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