Support for User JS scripts has been added to Chrome and the extension manager has been changed.

In the recent DEV build of Chrome, now User JS scripts are easy to install - as extensions



After clicking on Next, we are warned that scripts can harm your computer, we agree.

And there is a standard dialog like the installation of extensions

Extension Manager

As we know he is here.

or here chrome: // extensions /
Now the manager looks like this


Now you do not need the key - enable-user-scripts for user js
All this is added in 4.0.237.0

UPD
If you have the last byl cm above and the installation of scripts doesn't work at all, then see if the daw is removed