perf: optimize xterm.js rendering for Linux#1
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- Remove blanket CSS transparency on all xterm layers — this was forcing alpha blending every frame and defeating the WebGL renderer's opaque fast path. The terminal theme already provides matching background colors per preset. - Disable font ligatures (font-variant-ligatures: none) and use text-rendering: optimizeSpeed — ligature shaping in JetBrains Mono and Fira Code is expensive on Linux font stacks. - Add CSS contain: strict to the terminal container for layout isolation (skips layout/paint work outside the terminal). - Switch shell terminal dimming from CSS opacity + transition to filter: opacity() with will-change hint — avoids triggering a full compositor layer blend on every repaint. https://claude.ai/code/session_01FtXB5R8qjM54WqwE1FLCYJ
This was referenced Mar 19, 2026
This was referenced May 6, 2026
johannesjo
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May 15, 2026
…ck initial prompts (#107) * fix(prompt): scale bracketed-paste delay by line count to prevent stuck initial prompts When an agent enables bracketed paste mode (CSI ? 2004 h), synthetic prompt sends wrap the text in \x1b[200~...\x1b[201~ to avoid Codex's paste-burst guard. However, TUI agents like Claude Code process the paste asynchronously — if \r arrives while the paste is still being consumed, it is absorbed into the input buffer as a newline rather than submitting the prompt. The previous fixed 50ms delay was sufficient for short prompts but too short for large ones (e.g. a 31-line initial task prompt). The symptom is the agent sitting in INSERT mode with "[Pasted text #1 +N lines]" in its input, never sending. Fix: - Track bracketed paste mode (CSI ? 2004 h/l) in AgentTrackingState via updateBracketedPasteMode(), called on each PTY data chunk in markAgentOutput() - Export isAgentBracketedPasteEnabled() so sendPrompt can conditionally wrap - Scale the pre-Enter delay: max(50ms, lines * 15ms), capped at 500ms — a 31-line prompt now waits ~465ms instead of 50ms Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * test(prompt): add pasteDelayMs regression tests; export fn; fix duplicate constants Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> --------- Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
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forcing alpha blending every frame and defeating the WebGL
renderer's opaque fast path. The terminal theme already provides
matching background colors per preset.
text-rendering: optimizeSpeed — ligature shaping in JetBrains Mono
and Fira Code is expensive on Linux font stacks.
isolation (skips layout/paint work outside the terminal).
filter: opacity() with will-change hint — avoids triggering a full
compositor layer blend on every repaint.
https://claude.ai/code/session_01FtXB5R8qjM54WqwE1FLCYJ