Appearance
Scrollback
Scroll buffer behavior, reverse index, total line tracking, viewport auto-follow policy, and alternate screen interaction. Scrollback handling is one of the least standardized areas of terminal emulation — terminals differ in buffer size limits, whether alternate screen content enters scrollback, whether new output yanks a scrolled-up viewport back to the live bottom, and how reverse index interacts with scroll regions. Scrollback is the most implementation-specific area of terminal behavior. The ECMA-48 standard says nothing about scroll buffers — it's entirely a terminal emulator convention. Buffer sizes range from 0 lines (Alacritty's default was famously 0 on first release, fixed after user revolt) to 10 million+ (iTerm2). Kitty chose a different approach entirely: infinite scrollback stored efficiently on disk. The debate over whether the alternate screen should preserve scrollback, and whether output should auto-follow while the user is reading history, has generated more terminal GitHub issues than almost any other topic.
Analysis2026-05-17
The Scrollback category covers 10 features. Top performers (100%): Ghostty, Kitty, iTerm2, Terminal.app, Warp and 6 more. Common gaps: Alt screen separate scrollback (1 terminal fails).
Terminal Applications
Headless Backends
Parser correctness tested via Termless. A ✓ means the parser accepts the sequence, not that it renders correctly.