How to download a CRX using clients2.google.com?

Question

I have ran into some difficulties in the last week.I have been able to use the following link format to download a crx file using the ID of the extension listed on the chrome store. https://clients2.google.com/service/update2/crx?response=redirect&prodversion=68.0.3440.75&x=id%3D-ID-%26uc

Now any new chrome extension published to the chrome store in recent weeks the above link will not work. It will not download anything. After using fiddler it shows as a 204 code error. This link had worked for over 2 years but not anymore. It only works on extensions that have not been published in recent months.

Can anyone provide a work around?

I have tried the following but the ID in the extension once downloaded is different from the ID in the chrome store listing (I need them to be the same). https://clients2.google.com/service/update2/crx?response=redirect&os=win&arch=x86-64&os_arch=x86-64&nacl_arch=x86-64&prod=chromecrx&prodchannel=unknown&prodversion=83.0.4103.61&acceptformat=crx2,crx3&x=id%3D-ID-%26uc

Answer 1

The format of the x= parameter the end of the URL has changed slightly.

Here's an example that seems to be working for me (as of Mar 2021):

https://clients2.google.com/service/update2/crx?response=redirect&os=linux&arch=x64&os_arch=x86_64&nacl_arch=x86-64&prod=chromium&prodchannel=unknown&prodversion=91.0.4442.4&lang=en-US&acceptformat=crx2,crx3&x=id%3Dxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx%26installsource%3Dondemand%26uc

FWIW, trying to urldecode the string to x=id=blahblah&installsource=ondemand&uc, or removing the installsource= or uc parameters, will fail.