Multiple fallbacks for the same property name not working

[maxcelima]

Expected behavior:
When an array is used for the fallbacks value it should render multiple properties for the same property name

Describe the bug:
The array of fallbacks are being render like this:

.Component-withFallbacks-2-2-1 {
  0: [;
  1: o;
  2: b;
  3: j;
  ...
  29: c;
  30: t;
  31: ];
  display: flex;
}

The jss vendor prefix plugin seems to be changing it into the string
"[object Object], [object Object]"

Codesandbox link:
https://codesandbox.io/s/jss-fallbacks-problem-gbvkf

Versions (please complete the following information):

• jss: 10.0.0-alpha.24
• Browser: Chrome
• OS Windows and macOS

[kof]

I confirm, something in react-jss or in plugins breaks this, core works as expcted.

[kof]

Also it turns out to be a regression compared to v8

[kof]

Turns out we forgot to handle fallbacks in jss-plugin-vendor-prefixer after we decided to kick them out of vendor-prefixer as a jss specific syntax.

Now I wonder if fallbacks should be prefixed at all or left as-is.

[kof]

Made fallbacks to get prefixed.