Robuta

https://www.w3.org/WAI/GL/WCAG20/NOTE-WCAG20-TECHS-20090105/SCR2 SCR2: Using redundant keyboard and mouse event handlers | Techniques for WCAG 2.0 keyboard and mouse https://lists.w3.org/Archives/Public/w3c-wai-gl/2014OctDec/0159.html Re: Completing LC-2952/Proposal to remove SCR2 from David MacDonald on 2014-12-14... https://www.ncbi.nlm.nih.gov/Structure/pdb/1LY2 1LY2: Crystal structure of unliganded human CD21 SCR1-SCR2 (Complement receptor type 2) complement receptor type 22-acetamido-2-deoxy-beta-D-glucopyranose