How can I fix WebStorm warning "Unresolved function or method" for "require" (Firefox Add-on SDK)

Solution 1:

Do you mean that require() is not resolved? You need to either add require.js to your project or enable Node.js Globals predefined library in Settings/Languages and Frameworks/JavaScript/Libraries.

(Edited settings path by @yurik)

In WebStorm 2016.x-2017.x: make sure that the Node.js Core library is enabled in Settings (Preferences) | Languages & Frameworks | Node.js and NPM

In IntelliJ 2018.3.2+ go to Settings (Preferences) | Languages & Frameworks | Node.js and NPM and enable Coding assistance for Node.js

Solution 2:

Webstorm 11 and 2016.2.3

Enable Node.js Core library in Webstorm settings.

Solution 3:

After spending an hour trying to get this to work using all solutions found online, this finally did the trick!

File -> Invalidate Caches/Restart...

Solution 4:

In PHPStorm, it's a bit easier: you can just search for NPM in settings or:

File > Settings > Language & Frameworks > Node.js and NPM

Then click the enable button (apparently in new versions, it is called "Coding assistance for Node").