Multiplayer Sudoku is built on open-source software. These are the packages that run in your browser on this site, with their licenses.
iPhone photos (HEIC)
The sudoku solver opens iPhone photos with libheif and its HEVC decoder libde265, compiled for the browser by libheif-js. They are licensed under the GNU Lesser General Public License, version 3 (LGPL-3.0). They're loaded unmodified, as a separate file, only when you open such a photo. Their source code is here:
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