Caching of css background images

[madmacc]

It would be great if there was a way to cache CSS background images.
I currently have a lot of cards set up with dynamic background images like so:

<div #cardContainer class="permit"
      [ngClass]="{'permit-bkg-image': permitShowVirtualCardBgImage}"
      [ngStyle]="{
        'background': permitShowVirtualCardBgImage ? (tenant.style.permitBgColor ? tenant.style.permitBgColor + ', ' + permitBackgroundImage : permitBackgroundImage) : (tenant.style.permitBgColor ? tenant.style.permitBgColor : 'var(--ion-color-permit-card-bk-gradient)')
      }" 

I guess I could experiment with making the div an img-loader element and using imgAttributes but I was wondering if there was a better way to do this?

Thanks for the work on this it is really useful and works well!