Get the moqtap CLI

The WebTransport Inspector extension impairs a tab’s WebTransport traffic by sending it through the moqtap CLI, running on the same machine. The browser’s own network throttling has no effect on WebTransport, so this is how you watch your player on a bad network without changing the page or the player.

With the CLI running, pick a profile for the tab in the panel’s Impairment menu: Offline, 3G and 4G are free, with no sign-in. Pro adds your own scenarios, with the packet loss, delay and bandwidth you choose.

Install

macOS and Linux:

curl -sSf https://moqtap.com/install.sh | sh

Windows (PowerShell):

irm https://moqtap.com/install.ps1 | iex

Homebrew (macOS and Linux):

brew install moqtap/tap/moqtap

npm (macOS, Linux and Windows):

npm install -g moqtap

winget (Windows):

winget install moqtap.moqtap

The install scripts check each download against the release’s SHA256SUMS.

Or download a binary from GitHub Releases:

Platform	Architecture	Archive
Linux	x86_64	moqtap-x86_64-linux.tar.gz
Linux	ARM64	moqtap-aarch64-linux.tar.gz
macOS	x86_64	moqtap-x86_64-macos.tar.gz
macOS	Apple Silicon	moqtap-aarch64-macos.tar.gz
Windows	x86_64	moqtap-x86_64-windows.zip
Windows	ARM64	moqtap-aarch64-windows.zip

Start it for the extension

moqtap intercept --bridge

The CLI prints its identity when it starts. The first time, the extension shows the same identity and asks you to allow it. Keep the CLI running while you use impairment, then reload the page.

Impairing a Browser Tab covers profiles and permissions step by step, and the CLI reference lists every command and option.