I currently have a block with a simple grid which has 3 fields
Image (img_thumb)
Title (ttl)
Body (bdy)

I have no issues displaying the contents of the Title and Body, The image just prints out the field {img_thumb} in the rendered template. If I add prefix=“st:” it fails to render the ExpressionEngine content. it just prints out the entire code.
This is how I’m using it

{cards}
	<article id="w-node-019eb1c9-{bloqs:id}-{row_id}" class="service-card">
		<img src="{img_thumb}" loading="lazy" alt="{ttl}" class="service-card-img">
		<div class="service-card-contents">
			<div class="h3">{ttl}</div>
			<div class="spacer-m"></div>
			<div class="body-regular-medium">{bdy}</div>
		</div>
	</article>
{/cards}

I’ve attached 2 screenshots. the second one is the inspect in Chrome showing the {img_thumb} being rendered. Another weird bug is if I do

{img_thumb}
<img src="{url}" loading="lazy" alt="{ttl}" class="service-card-img">
{/img_thumb}

I’m able to see the image in the template, however it stops rendering the rest of the code. So the Title and Body aren’t showing

I was able to get it to work. Which i don’t think it’s ideal by wrapping the entire code in within the image tag

{cards}
	{img_thumb}
	<article id="w-node-019eb1c9-{bloqs:id}-{row_id}" class="service-card">
		
		<img src="{url}" loading="lazy" alt="{ttl}" class="service-card-img">
		
		<div class="service-card-contents">
			<div class="h3">{ttl}</div>
			<div class="spacer-m"></div>
			<div class="body-regular-medium">{bdy}</div>
		</div>
		
	</article>
	{/img_thumb}
{/cards}

Sorry for the mouth full. trying to be thorough.
Regards
Kevin