See commands

Viewport, emulation and screenshots.

See commands are about how the page renders — like Act, they run through the compatibility bridge, and promote the tab on first use.

Command	What it does
`viewport mobile\|desktop\|<W>x<H> [--dpr <n>] [--touch]`	Sets the viewport. `mobile` = 390x844 @3x with touch. `desktop` = 1440x900 @1x.
`emulate --color-scheme light\|dark [--reduced-motion] [--locale] [--timezone]`	Emulates rendering conditions.
`screenshot [--full] [--element <id>] [--out <file.png>]`	Captures a PNG. Without `--out`, jawb writes `./jawb-<tab>-<rev>.png`.

$ jawb viewport mobile --quiet
warning: tab promoted to bridge
viewport 390x844 @3.0x, mobile, touch (1170x2532 device px)
+ [295] link "Windows 64-bit" -> https://go.dev/dl/go1.27.1.windows-amd64.msi
...
  ... 239 changes in total (raise --diff-limit)
rev 1 → 2 (bridge, 131ms)

$ jawb screenshot --out ./see-go-dev-mobile.png
saved C:\...\see-go-dev-mobile.png (1170x2532 px, 246040 bytes, rev 2, bridge, 268ms)

$ jawb viewport desktop --quiet
viewport 1440x900 @1.0x (1440x900 device px)
rev 2 → 3 (bridge, 128ms)

$ jawb screenshot --out ./see-go-dev-desktop.png
saved C:\...\see-go-dev-desktop.png (1440x900 px, 98184 bytes, rev 3, bridge, 77ms)

Switching viewport re-observes the page: elements hidden at the new size report state: [] -> ["hidden"], new elements (like the mobile-only download links above) show up as added, and the diff can be large. It is capped at 50 entries (viewport has no --diff-limit); run jawb observe --full afterwards to see the whole page.