Fixes#2558
Codex uses alternate screen mode (CSI 1049) which, per xterm spec,
doesn't support scrollback. Zellij follows this strictly, so users can't
scroll back through output.
**Changes:**
- Add `tui.alternate_screen` config: `auto` (default), `always`, `never`
- Add `--no-alt-screen` CLI flag
- Auto-detect Zellij and skip alt screen (uses existing `ZELLIJ` env var
detection)
**Usage:**
```bash
# CLI flag
codex --no-alt-screen
# Or in config.toml
[tui]
alternate_screen = "never"
```
With default `auto` mode, Zellij users get working scrollback without
any config changes.
---------
Co-authored-by: Josh McKinney <[email protected]>
Add metrics capabilities to Codex. The `README.md` is up to date.
This will not be merged with the metrics before this PR of course:
https://github.com/openai/codex/pull/8350
The transcript viewport draws every frame. Ratatui's Line::render_ref
does grapheme segmentation and span layout, so repeated redraws can burn
CPU during streaming even when the visible transcript hasn't changed.
Introduce TranscriptViewCache to reduce per-frame work:
- WrappedTranscriptCache memoizes flattened+wrapped transcript lines per
width, appends incrementally as new cells arrive, and rebuilds on width
change, truncation (backtrack), or transcript replacement.
- TranscriptRasterCache caches rasterized rows (Vec<Cell>) per line
index and user-row styling; redraws copy cells instead of rerendering
spans.
The caches are width-scoped and store base transcript content only;
selection highlighting and copy affordances are applied after drawing.
User rows include the row-wide base style in the cached raster.
Refactor transcript_render to expose append_wrapped_transcript_cell for
incremental building and add a test that incremental append matches the
full build.
Add docs/tui2/performance-testing.md as a playbook for macOS sample
profiles and hotspot greps.
Expand transcript_view_cache tests to cover rebuild conditions, raster
equivalence vs direct rendering, user-row caching, and eviction.
Test: cargo test -p codex-tui2
This eliminates redundant user documentation and allows us to focus our
documentation investments.
I left tombstone files for most of the existing ".md" docs files to
avoid broken links. These now contain brief links to the developers docs
site.
James Peter