Umb V13.6.0, Slimsy V5.1.2 Using an Image block in a BlockGrid, I'm finding the images displayed in the back office appear to be low res while they look fine on the site itself. The relevant image block code is this:-

if (Model.Content.Image is MediaWithCrops theImage) {
                <slimsy-picture media-item="@theImage" css-class="lazyload img-fluid" crop-alias="@crop" render-lqip="true" alt-text="@(string.IsNullOrEmpty(imageAltTag) ? "Image Description Missing" : imageAltTag)" size="auto"></slimsy-picture>
}

I'm also using the Umbraco.Community.BlockPreview V1.12.2 package and the Badgernet.Umbraco.WebPicAuto V1.1.5 package for image upload resizing. Any clues would be appreciated. Thanks.

Does the back office load the JS slimys needs? As your have lqip set to true

Well the partial does have

@using Slimsy

&

@using Slimsy.Extensions

. In the end I decided to detect preview mode with:-

var isBackoffice = false;
if (UmbracoContextAccessor.TryGetUmbracoContext(out var umbracoContext)) {
        isBackoffice = umbracoContext.InPreviewMode; // True in the backoffice preview
}

and switch out Slimsy for the back office. Seems to work. Though I don't recall having to do that before in other projects.