UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/58.0.3029.110 Chrome/58.0.3029.110 Safari/537.36

Steps to reproduce the problem:
1. install an extension that disables the download shelf
2. write another extension and do: chrome.downloads.setShelfEnabled(true)

What is the expected behavior?

What went wrong?
setShelfEnabled doesn't have a callback function, so I can't check for lastError.

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 58.0.3029.110  Channel: n/a
OS Version: 
Flash Version: Shockwave Flash 24.0 r0

I'm still new to Chrome extensions, but every source tells me to check for lastError in the callback function. Please tell me if there is another way.