: This is a custom data attribute typically used by a JavaScript library or WordPress plugin to identify images that should have a "fallback" mechanism. If the primary lazy-loading script fails or if JavaScript is disabled, this attribute helps the system know how to handle the image display.
: This class specifically identifies the image as a thumbnail within a slider or carousel generated by the WP Post Slider and Carousel plugin. Why They Are Used <img data-lazy-fallback="1" class="wppsac-post-...
: By lazy loading these images, the browser doesn't have to download all slider images immediately, which speeds up the initial page load. : This is a custom data attribute typically
If you are seeing this code and your images aren't loading correctly, it is often due to: How disable lazy load for a specific image - GeneratePress Why They Are Used : By lazy loading