$ curl cheat.sh/
# firefox
# A free and open source web browser.
# More information: <https://developer.mozilla.org/en-US/docs/Mozilla/Command_Line_Options>.

# Launch Firefox and open a web page:
firefox https://www.duckduckgo.com

# Open a new window:
firefox --new-window https://www.duckduckgo.com

# Open a private (incognito) window:
firefox --private-window

# Search for "wikipedia" using the default search engine:
firefox --search "wikipedia"

# Launch Firefox in safe mode, with all extensions disabled:
firefox --safe-mode

# Take a screenshot of a web page in headless mode:
firefox --headless --screenshot path/to/output_file.png https://example.com/

# Use a specific profile to allow multiple separate instances of Firefox to run at once:
firefox --profile path/to/directory https://example.com/

# Set Firefox as the default browser:
firefox --setDefaultBrowser

$
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