For example I would like to pass a start/opening url to firefox.

When I try to pass an argument it looks like this:

npx extension dev --browser=firefox -- "https://en.wikipedia.org/"
►►► Downloading extension...
URL https://en.wikipedia.org/
►►► Unpackaging browser extension...
PATH /home/jono/src/savr/ff-two/David_Bowie
ERROR in Extension.js ✖︎✖︎✖︎ Failed to download or extract ZIP file. Error: ADM-ZIP: Invalid or unsupported zip format. No END header found
at Object.INVALID_FORMAT (/home/jono/src/savr/ff-two/node_modules/adm-zip/util/errors.js:56:16)
...