Ghostty 1.4.0: Release Overview

Released: October 27, 2026

Ghostty 1.4.0 represents a significant milestone in the project's evolution. This major update introduces substantial optimizations for memory and performance, achieves a landmark 100% implementation of the Kitty graphics protocol (including relative placements and animations), enhances SSH integration, and delivers hundreds of refinements across all supported operating systems.

This version is the culmination of seven months of intensive development, featuring contributions from 172 developers across $\approx 2,889$ commits.

A Note from the Team: We extend our deepest gratitude to the maintainers, community moderators, translators, packagers, and users. These notes were meticulously hand-crafted by the Ghostty maintainers to ensure a detailed changelog.

🛡️ Security Advisories

This release addresses several critical vulnerabilities. While the maintainers have requested CVEs from GitHub, they are currently pending assignment.

Critical Fixes

Paste Protection: Fixed an issue where carriage returns weren't treated as line endings, potentially allowing commands to execute without confirmation in non-bracketed paste environments.
Kitty Graphics Exploits: Patched vulnerabilities where malicious commands could cause hangs, crashes, massive memory allocations, or unauthorized file access outside temporary directories.
Tmux Control Mode: Resolved two separate issues where malicious output or specific layout configurations (zero-sized/oversized panes) could crash all Ghostty windows.
Scrollback Corruption: Fixed a memory corruption bug triggered when clearing the screen into scrollback if the cursor held a hyperlink or style (specifically when scrollback-limit was set to 0).
Zsh Integration: Prevented a flaw where crafted directory names could trick zsh into sending arbitrary escape sequences (e.g., using OSC 52 to silently overwrite the clipboard) during a cd command.
Hyperlink Safety:
- OSC 8: Blocked unsafe local files and added confirmation for custom URL schemes to prevent arbitrary command execution.
- Link Config: Applied the same protections to links detected via the default URL matcher.
Drag-and-Drop: Fixed a bypass where dragging text skipped paste protection.
File Execution: Prevented a vulnerability where control characters in a filename could mislead the user into confirming one command while executing another.

🍎 macOS 27 "Golden Gate" Support

Ghostty 1.4 now fully supports macOS 27. Most updates focused on visual and behavioral compatibility.

Visual & Functional Improvements

Titlebar Tabs: When using macos-titlebar-style = tabs, layout issues have been resolved.
Theming: The native tab bar no longer renders as a solid gray block; it now correctly integrates the glass style with the terminal background.
Transparency: Setting macos-titlebar-style = hidden no longer clips the top of the terminal when "Reduce Transparency" is enabled.
Shortcuts: Fixed a bug where the "New Window" action would spawn two windows if no Ghostty instances were currently open.

Compatibility Matrix

OS Version	Support Status	Notes
macOS 27	✅ Full	Optimized for Golden Gate
macOS 13-26	✅ Full	Fully backward compatible
macOS < 13	❌ Unsupported	Not supported in 1.4.0

Note: While Ghostty 1.3.1 runs on macOS 27, users will encounter the visual glitches (like the gray tab bar) mentioned above.

🎨 Kitty Graphics: 100% Specification Coverage

Ghostty is now the first terminal emulator outside of Kitty itself to implement the full Kitty graphics specification.

New Capabilities

Animations: Support for animated images (e.g., GIFs via kitten icat).
- Full control over frame transmission and playback.
- Animations automatically pause when the terminal is not visible.
Relative Placements: Programs can now anchor one image relative to another, ensuring child images move in tandem with their parents.

Technical Refinements

The team performed a comprehensive conformance pass to eliminate behavioral discrepancies:

Images now correctly scroll within scroll regions.
Retransmitting an image ID now properly replaces the existing image.
Invalid data now triggers an error response rather than leaving the client hanging.

Performance Boost

Image payloads are now processed using SIMD (Single Instruction, Multiple Data) rather than byte-by-byte parsing.

$\text{Parsing Speedup} \approx 16\times$ (Based on 64 MiB of image data on x86_64 Linux)

# Example: Displaying an animated GIF using the Kitty protocol
kitten icat animated_image.gif

💾 Memory Management & Scrollback

Ghostty 1.4 introduces a transparent compression system for non-visible scrollback history.

How it Works

The terminal monitors activity and compresses history pages during idle periods. When a user scrolls up or performs a search, these pages are decompressed on demand.

Impact on Resources

Physical Memory: Typical text-heavy history now consumes $70\%$ to $90\%$ less resident memory.
Capacity: Because of this efficiency, the default scrollback limit has been increased:
- ~~10 MB~~ $\rightarrow$ 50 MB per terminal.

Important: This optimization reduces resident (physical) memory, not virtual memory. To see the benefits, monitor the resident set size (RSS).