Bugzilla newbie here. Probably an old bug. I first noticed it in WebKit.app nightly build r31224. It continues onward with r34469. Mac OS X 10.4.11 on a MacBook 2 GHz with 3 GB RAM. Problem: Unlike Safari 3.1.1, WebKit nightly build will not allow creating a new tabbed window with a linked page by Command - Single Clicking on a link. The user is forced to instead Command - Double Click the link as a workaround to get the required response. (Note that Single Clicking any link to change the current tab to that linked page works without any problem).
This sounds like something that would be caused by a Safari enhancer of some sort, which is not compatible with new WebKit. Could you please try removing any that you may have?
I cannot confirm the problem.
I had this same issue, and figured out the problem. For me, it was not a Safari-specific add-on, but a system-wide tool called ICeCoffEE. http://web.sabi.net/nriley/software/ I had version 1.4.3 (old). As soon as I turned it off, the problem disappeared. I updated to 1.5b4, and everything worked fine. So, check for ICeCoffEE and update as needed.
ICeCoffEE 1.4.x allows you to Command-click text in WebKit to launch the selected URL (or Command-option-click to pop up a menu, etc.). ICeCoffEE 1.5.x allows you to Command-click WebKit text to launch the URL surrounding that point; you don't need to select it first. This works in Safari, Mail and nearly anywhere that uses WebKit (including when WebKit is being used as an editor). In either version, if what you're clicking is a link in non-editable text, ICeCoffEE should detect the situation and not activate. Unfortunately, ICeCoffEE needs to rely on some non-public (and thus volatile) WebKit API. I've tried to restrict my use of it to as little as possible, but because the WebKit internals have changed a few times, you'll need to use the newest version — which is compatible with Safari 3.0 through the current WebKit trunk. If you ever have problems with ICeCoffEE WebKit support, please let me know (icecoffee@sabi.net). I do know of one cosmetic bug with the selected text being offset (though the correct URL should launch). This is WebKit bug 18794. Also, I intercept Command-clicks on plugins; this is wrong and I'll fix it in the next version. I do plan to remove the "Sorry, ICeCoffEE was unable to find any text to select." dialog in the next version as it can be rather annoying and is pretty pointless. Sorry for hijacking this bug; in case someone searches for it I just want to make sure they don't annoy the WebKit folks about a bug that isn't theirs.