When upgrading to Claude 3.7 Sonnet, a performance bottleneck emerged in the Diff Viewer, causing browser freezes when many files were modified due to the simultaneous loading of multiple CodeMirror instances. Each instance took 20-50ms to load, creating long blocking tasks, especially when 15 or more editors loaded concurrently. This was further exacerbated by forced reflows during CodeMirror's initialization, a known issue. Several potential solutions were considered, including collapsing files by default or using an intersection observer, but these either required manual intervention or introduced complexity. Ultimately, a time slicing approach was adopted, which involved batch loading two files at a time, using placeholders for others, and implementing small delays between batches to maintain browser responsiveness. This strategy transformed a single long task into multiple shorter ones, improving both performance and user experience by allowing content to appear progressively and naturally, thus preventing the jarring effect of all diffs expanding simultaneously.