The highlighting algorithm does not repeat matched terms in the same paragraph. This is similar to how Wikipedia does not repeat linked topics in the same article. A bug in the implementation breaks this slightly. Highlighted terms in the same paragraph are repeated if the terms are separated by a longer term. This is apparent in short, frequently used terms. The solution is to be discussed: Either highlight all matches in the entire paragraph (easy change), or rewrite the matching algorithm to skip repeated terms.
See #11