Terminal, layouts, and highlighting
The terminal is xterm.js rendered with WebGL (falling back to DOM rendering where WebGL is unavailable), fed raw bytes by the broker's synchronous render path. Nothing DRAGON does — capture, redaction, inference, highlighting — sits between device output and the screen.
Grid layouts
Split the terminal pane into tiles from the window icon at the right end of the tab strip, Windows-snap style. Four layouts ship in v1.3.0:
- Single — the classic full-pane terminal, rendered exactly as before grids existed.
- Side by side — two tiles, 1×2.
- Stacked — two tiles, 2×1.
- Grid — four tiles, 2×2.
Each tile is a full terminal with its own PTY size and its own scrollback (5000 lines). Exactly one tile is focused at a time, marked by an accent border. The focused tile drives everything session-scoped: the tab strip, the copilot context, the inline ask bar, and the staging strip all follow it. Clicking a tile — or any keyboard focus landing in it — moves focus.
Opening a session in a split layout fills the first empty tile in reading order rather than hiding as a background tab or evicting the tile you're viewing; the focused tile is only replaced when the grid is already full. Closing the focused tile moves focus to the nearest occupied tile rather than leaving a dead pane. Each tile is wrapped in an error boundary, so a fault in one view degrades to a recoverable in-place notice while the rest of DRAGON keeps running.
Light and dark themes
DRAGON's dark theme is the default and the brand baseline. A sun/moon control in the tab bar — or Settings → Appearance — switches instantly to a full light mode that keeps the same grayscale-first, accent-colored aesthetic, including the terminal itself: the light terminal darkens the ANSI hues so color-coded device output (up/down, ok/error) stays legible on a light surface instead of washing out. The choice persists across launches. Theming is applied at the renderer, never by rewriting the byte stream, so captured records are unaffected.
Keyword highlighting
Keyword highlighting is a single on/off toggle in Settings → Appearance, off by default. Enabled, it applies the built-in error-and-status coloring: syslog severities 0–2 (emergency, alert, critical) highlight the whole line in red; error, down, and err-disabled tokens highlight red; up and complete highlight green.
Highlighting is rendered via xterm decorations, never ANSI injection into the byte stream — the render-path invariant holds, and captured records are unaffected.
The per-rule custom highlight packs that appeared in
v0.2.2were removed inv0.3.0in favor of this single toggle. Configurable rules may return in a later release.
In-terminal copilot affordances
Two copilot entry points live directly on the terminal surface — the // inline ask bar and the "✦ Ask about this" selection affordance. They are documented with the rest of the copilot in copilot and RAG.
Scrollback and reattach
Live sessions survive a page reload: when a webview reattaches, scrollback is replayed from the session's raw log, so the terminal picks up where it was. Raw logs rotate at a maximum size per session — see session and capture.