CrossCheck: Combining Crawling and Differencing to Better Detect Cross-browser Incompatibilities in Web Applications

One of the consequences of the continuous and rapid evolution of web technologies is the amount of inconsistencies between web browsers implementations. Such inconsistencies can result in cross-browser incompatibilities (XBIs)--situations in which the same web application can behave differently when run on different browsers. In some cases, XBIs consist of tolerable cosmetic differences. In other cases, however, they may completely prevent users from accessing part of a web application's functionality. Despite the prevalence of XBIs, there are hardly any tools that can help web developers detect and correct such issues. In fact, most existing approaches against XBIs involve a considerable amount of manual effort and are consequently extremely time consuming and error prone. In recent work, we have presented two complementary approaches, Web Diff and Cross T, for automatically detecting and reporting XBIs. In this paper, we present Cross Check, a more powerful and comprehensive technique and tool for XBI detection that combines and adapts these two approaches in a way that leverages their respective strengths. The paper also presents an empirical evaluation of Cross Check on a set of real-world web applications. The results of our experiments show that Cross Check is both effective and efficient in detecting XBIs, and that it can outperform existing techniques.