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Increasing the priority of a resource usually comes at the cost of another resource, so Priority Hints should be used sparingly. However, if the browser is queuing your LCP image, I recommend you experiment with Priority Hints to see if you can reduce this waiting time and improve your LCP.
Jeremy Wagner
New field insights for debugging INP
Interaction to Next Paint (INP) is a Core Web Vital that measures how responsive a page is to interactions. Due to INP's scope, it can be difficult…
Let's say a SPA first load has been optimized with SSR and the LCP image is loaded pretty fast because it's in the HTML.
But the JavaScript then builds a carousel in the DOM, which initially shows the very same image.
I guess there's a second render of the image. How can I check this easily?
Would it make sense that the LCP takes the late second render of the image, instead of the fast first one?
Apparently, an image whose part above the fold is indeed the largest, but of which only a small part can be seen, can be considered an LCP element, even if another image has a larger part visible... 😭
You can see this for my photography site in this WebPageTest result:
https://www.webpagetest.org/vitals.php?test=230606_BiDcN4_4NJ&run=3&cached=0#lcp
Watch Out for Layout Shifts with ‘ch’ Units
In our case, we were using ch units to define our page layout. This meant that our post content was equal to 50ch units (or the width of fifty…
Limiting the image density on mobile devices drasticaly improves performance, with no visual loss, so we did it!
I still wish it was much easier than dealing with <picture> and x descriptors for fluid images… 😞
With a <img maxdensity="2.5" …> attribute for example!
If you agree, comment:
https://github.com/whatwg/html/issues/4421
Kevin Farrugia 
Paul Hebert