"Middle mouse button is ignored"
Middle mouse button functionality IS working like FireFox since 0.x years ago. So it looks like something is not setup correctly. Probably you have a Logitech mouse with IntelliPoint software installed which will not let the middle mouse button work as it should?
"Prompt windows block the whole browser"
This will only block the current tab, since a couple of versions before. Very handy.
You can also view headers, maybe not as good as "Live HTTP Headers":
1. CTRL + SHIFT + I (Developer tools)
2. Resources tab, activate
3. Select the resource, html source, or other media on the site
4. Goto headers 'tab'
You can change the user agent with extensions:
chrome.google.com/extensions/search
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You can use a HTML validator extension:
chrome.google.com/extensions/search
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So it looks like this post is not up to date. I am using Chrome since a long time. And every version it get better :)
You can download the newest 'developer' version here (auto install):
dl.google.com/chrome/install/375.29
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