Outputting [Object object] instead of URL for CSS file url functions

[IronSean]

• Operating System: Windows 10
• Node Version: v12.13.1
• NPM Version: 6.12.1
• webpack Version: 4.41.4
• file-loader Version: 5.0.2

Expected Behavior

generate CSS like this (as it did in file-loader 4.x):

body {
    background: url(http://localhost:8080/dist/bce4508….png) #ffffff;
}

Actual Behavior

generates CSS as

body {
  background: url([object Module]) #ffffff;
}

Code

The use of file-loader is completely default currently, I'm working on a repro below as the whole webpack config is quite large.

How Do We Reproduce?

I'm working on a repro I can provide.

[alexander-akait]

update css-loader to latest version, or you can disable ES module syntax using esModule: false