Unknown argument: firefox

[Saphareas]

Is this a feature request or a bug?

It's a bug (I think).

What is the current behavior?

I've set the path to my Firefox using the WEB_EXT_FIREFOX environment variable.
Now when running web-ext build it just prints the help followed by Unknown argument: firefox

What is the expected or desired behavior?

web-ext build should just ignore the argument and run.

Version information (for bug reports)

• Firefox version: 64.0b11 (64-Bit) Dev Edition
• Your OS and version: Kubuntu 18.10
• Node version: v8.11.4
• npm version: 6.4.1
• web-ext version: 2.9.1

[Rob--W]

This seems like a duplicate of #793.

As a work-around, you could use a .web-ext-config.js file, see https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/Getting_started_with_web-ext#Setting_option_defaults_in_a_configuration_file and https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/Getting_started_with_web-ext#Automatic_discovery_of_configuration_files