Some extensions/themes get 401

[ojoched]

Example: dliacmdfmjlmeelgfohdfincmelhdcnd
Generated url: https://clients2.google.com/service/update2/crx?response=redirect&os=win&arch=x86-64&os_arch=x86-64&nacl_arch=x86-64&prod=chromiumcrx&prodchannel=unknown&prodversion=52.0.2743.116&acceptformat=crx2,crx3&x=id%3Ddliacmdfmjlmeelgfohdfincmelhdcnd%26uc

Returns 401 despite being listed.

[scout0773]

The extension is not available.

Edit: If the extension is installed, you can find the source manually.
Windows: C:\Users\Username\AppData\Local\Google\Chrome\User Data\Default\Extensions
Linux: ~/.config/google-chrome/Default/Extensions/
MacOS: ~/Library/Application\ Support/Google/Chrome/Default/Extensions