I just launched my new site and, despite the fact that in several browsers, to notice how it works, I noticed something strange.

Do you see a gap after the word “but”? According to my reasoning, the word "was" on the next line should be next to it, since there is enough space for this, but, as you can see, this is not so.
Although this screenshot is from Firefox (10), I get the same in Chrome (17) and Internet Explorer (9).
Using Firebug to test an item, it shows between “was” and “disappointed” (which explains why it is not on the line above), but when viewing the source there isn’t such one.
This makes me assume that the browser inserts them, but I have no idea why.
, http://limeblast.co.uk/2012/02/currently-playing/