This study suggests the need for best practices, specialized tools and standards, and targeted outreach related to Web-based content cited in theses. It analyzes citation practices in a corpus of master's theses in performance studies published at Texas A&M University from 2012 to 2020. Finding that only a slim majority of Web-based material cited in the theses remains fully functional within a decade of citation, this study confirms that "Web at large" content poses the greatest risk of irretrievable loss. Additionally, it considers actions by student authors that make theses vulnerable to evidentiary loss or change. A deeper understanding of the fragility of Web-based content and the potential for mitigation can inform needed interventions by librarians and other partners in graduate research.