I also do that. Once in a while you get text with a colon in it, which Chrome interprets as a protocol handler and goes to about:blank. 1 in a thousand but it still gets me often. Here is a test.
Any idea if this exists for Firefox? I've been looking for it for a while. It's the major feature I miss from Chrome. I've had enough of Ctrl-C, Ctrl-T, Ctrl-V.
Highlight any text and right-click. The third option down will offer to search Google using the selected text (though it probably uses your default search engine, rather than hardcoding Google).
You can also highlight any URL (it doesn't need to be a link, just look like a URL) and tell Firefox to load it by either right-clicking or by dragging it to the tab bar. Try it out on any of the following:
I drag selected text to between tabs to create a new tab with a Google search for that text. I do that a lot.