Hello friends, In this post, I'll show you, how you can hide footer of Quick action and adjust the content height of model popup using css in Lightning component. In many use-cases we don't need extra space available in quick action popup window, so to narrow down the extra space and also hide footer of popup window you can go through this post. 

Hide footer and adjust height of quick action popup

Normally the quick action popup window looks like below image,

Use following css code to adjust height and hide footer of quick action popup.

QuickAction.cmp

 <aura:component implements="flexipage:availableForAllPageTypes,force:lightningQuickAction" access="global">    
    <aura:html tag="style">
        .slds-modal__footer{
        display:none !important;
        }      
        .slds-modal__content{
        height:initial !important;
        max-height:190px !important;
        }
    </aura:html>
    <center>
        Quick action window with modified height and footer.
    </center>
 </aura:component>

Note: Please note, the above code should be placed inside your component(html part) , not in the stylesheet file of component.

Output:

Hope you like this post, for any feedback or suggestions please feel free to comment. I would appreciate your feedback and suggestions.
Thank you.