Occasionally one wishes to set systemwide parameters for an application, such as a contact address for email, an application name, or setting an option that guides major behavior. Yii provides for setting of static parameters in the configuration file, and this article talks about how to do it conveniently.
So you want to use a fork of any existing vendor extension with your Yii 2 install and use the fork, instead of original source. This does not need you to push any update or register your package on packagist.org. You are recommended to follow the approach below:
I recently had to have a checkbox column in my grid view that supported the 'disabled' attribute. This was easy enough to do by extending the CCheckBoxColumn. However, I also wanted the checkbox to be selected when clicking on the table's row (supported via CGridView's selectableRows option). I discovered I had to tweak yiigridview.js so that it would not select disabled rows when clicking on it or on the 'select all' checkbox.