dynamics-crmsubgridcrm-ribbon-workbench

How to add a custom button on CRM subgrid?

I have two entities in my Dynamics CRM solution. Both are related to each other. Product -> configurations

Each product can have multiple configurations. I have added a subgrid on product screen.

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I need to call a custom html webresource to be able to create configuration records.

How to add a custom button to the subgrid? OR how to customize existing (+) button to open an html webresource?

Solution
    1. Add the entity to a solution & take a backup
    2. Open the solution in Ribbon workbench
    3. Start customizing the subgrid ribbon (ignore other two - Main grid & Form), right click the OOB button & hide it (this is also a backup)
    4. Add a new button & custom javascript action command (follow this)
    5. Open your custom HTML webresource using openWebResource method in javascript function