I've tried Sage twice but have found the documentation lacking both times. I ended up going back to the individual programs that make it up (Octave,R) and an easier computer algebraic system (mathomatic).
They're not random, they're at 75 characters! But granted, it does make it difficult to read. Transforming between soft line breaks and no line breaks is a trivial ignored computing problem in my opinion.
I suggest that one not use bookmarklets without examining them first, confirming for oneself that the are safe. Fortunately, this one's very brief and apparent.