Kilotest: Diagnoses of attribute value invalid violation by HTML element 755 on Prometheus page

Here is how tools diagnose the attribute value invalid issue for HTML element 755 of the Prometheus page.

Basics

• About the attribute value invalid issue
  • Why it matters: Item behaves improperly
  • Priority: highest
  • Related WCAG standard: 1.3.1
• About the Prometheus page
  • URL: https://www.joinprometheus.org/
  • Tested on 2026-04-07 at 19:19
• About HTML element 755
  • Tag name: IMG
  • Text: [not applicable]
  • Start tag: <img loading="lazy" sizes="140px" srcset="https://static.wixstatic.com/media/b5cd7f_ead0fc9cb42240d1a9e31dfb0ed37316~mv2.png/v1/fill/w_140,h_90,al_c,q_85,usm_0.66_1.00_0.01,enc_avif,quality_auto/Sammy%20Logos%20to%20Update%20(560%20%C3%97%20360%20px).png 1x, https://static.wixstatic.com/media/b5cd7f_ead0fc9cb42240d1a9e31dfb0ed37316~mv2.png/v1/fill/w_280,h_180,al_c,q_85,usm_0.66_1.00_0.01,enc_avif,quality_auto/Sammy%20Logos%20to%20Update%20(560%20%C3%97%20360%20px).png 2x" id="img_comp-lh9e5zj9" src="https://static.wixstatic.com/media/b5cd7f_ead0fc9cb42240d1a9e31dfb0ed37316~mv2.png/v1/fill/w_140,h_90,al_c,q_85,usm_0.66_1.00_0.01,enc_avif,quality_auto/Sammy%20Logos%20to%20Update%20(560%20%C3%97%20360%20px).png" alt="The Marcy Lab School Logo" style="object-fit:cover" class="BI8PVQ Tj01hh" width="140" height="90">
  • XPath: [not obtained]
  • Bounding box: x = 1308, y = 1433, width = 140, height = 90

Diagnoses

1. Bad value for attribute srcset on element img: Expected width descriptor but found 1x at …0%20px).png 1x,. (When the sizes attribute is present, all image candidate strings must specify a width.)

   Tool: Html Checker API (World Wide Web Consortium)