A Taxonomy of HTML5 Canvas Bugs

Abstract

The HTML5 <canvas> is widely used to display high quality graphics in web applications. However, the combination of web, GUI, and visual techniques that are required to build <canvas> applications, together with the lack of testing and debugging tools, makes developing such applications very challenging. To help direct future research on testing <canvas> applications, in this paper we present a taxonomy of <canvas> bugs. First, we extracted 2,403 <canvas>-related bug reports from 123 open source GitHub projects that use the HTML5 <canvas>. Second, we constructed our taxonomy by manually classifying a statistically representative random sample of 332 bug reports. Our manual classification identified five broad categories of <canvas> bugs, such as Visual and Performance bugs. We found that Visual bugs are the most frequent (35%), while Performance bugs are relatively infrequent (5%). We also found that many <canvas> bugs that present themselves visually on the <canvas> are actually caused by other components of the web application. Our taxonomy of <canvas> bugs can be used to steer future research into <canvas> bugs and testing.