Complex sentence: During this period of inactivity, Cleveland Municipal Stadium was demolished and the new Cleveland Browns Stadium (now FirstEnergy Stadium) was built on the site, and the late Al Lerner, a former friend and business partner of Art Modell's, was approved as owner.
Split into simpler sentences: During this period, Cleveland Municipal Stadium was demolished and Cleveland Browns Stadium (now FirstEnergy Stadium) was built on the site. The late Al Lerner, a former friend and former business partner of Art Modell's, was approved as owner.