<snapdata remixID="8927095"><project name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" version="1"><notes></notes><thumbnail>data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAKAAAAB4CAYAAAB1ovlvAAAFf0lEQVR4Xu3dz2scdRjH8aci1LZCUiVFD+IpF/EfkOJWQgmVQk7aXhQaRYk9iNhLwRRTkkAvikf/DimCgh42KIIFzcUfJxEPKrnYg62/cGU2sru6UfL9fJ7Ozk7eC7nN55mZZ177nWHmu5NDvV6vF3ymugNff7QVd514IObn56duPw4BcOqO2Z4b/OPSQnzz1Zfx0Pln4vPjJ+Lkcy/E7Oxs43cOgI0/RPvbwO3t7bj19Jl47OjhQeD6n3fHmRdX4t1jx2Np+fn9Fap5KQDW3PA7uboPL70cCx+8M7aK737/I354/HR8v/BkLJ07fyc3obg2AItb1szA7Y+34sjFZ/sb91uvF+/f92CcfOpcfDr/aCwuLjZzoyMCgI09NPvfsM+2unFj5UIsv3Qx3rv3/jh7YXn/4QkvCcAJH4CDvnoAHnQBE95/AE74ABz01QPwoAuY8P43DuDG+tXYXF8rbsvtRx4uzmzs/BSbOzeLcq/NzcTqXPkN3iNffFu0nmphZV3KPlXrUvoXK69E/8/4ABCAfT4A/PtbxAg4HE4YAY2hVY0CEICqnZQcAAGYAkktAkAAqnZScgAEYAoktQgAAajaSckBEIApkNQiAASgaiclB0AApkBSiwAQgKqdlBwAAZgCSS3SfeNadN+8psbJ1diBzquXo3PpsrXGxk1GiLffiv5f4aeNs02UmS3K8+Oq1VL/rqzF6pXXC4/UPxcHYOHUKgVF1XJltomyLgBa34fYHf0YAftdBKCLSckDcNA1ACqA3AwAAegasvIABKAFyA0DEICuISsPQABagNwwAAHoGrLyAASgBcgNAxCAriErD0AAWoDMMJMRzAbWGG/lZASmYw0FKc91lacn1RqVZ9W8mmPk2640UDlYCopqM6XZJsJ7aJR9AuAIJEZARsAaryLGVwVAAALwfzrAKXikObyebdgMrgF3e8E1oDl+cgrmFGwS8uIABKAnyEwDEIAmIS8OQAB6gsw0AAFoEvLiAASgJ8hMAxCAJiEzznSsQQOVe3q13ijnzQhD7G182A9AczCT4oyAjIASnKwQAAGYZUmqA0AASnCyQgAEYJYlqQ4AASjByQoBEIBZlqQ6AASgBCcrBEAAZlmS6gAQgBKcrBAAAZhlSaoDQABKcJJCvJojqZE1lOHVHCNN5ldxu81QJjBUOaV/vJoDgGPjHADNoZ8JqcMGKnP7AAjAPTvQxvmKnII5BXMKNge88QauX43N9bXisspFtHK6Uk6L1c4wAu59SBv3zwq5BuQasHj0yQwAEICZnoprARCAxWgyAwAEYKan4loABGAxmswAAAGY6am4FpMRils2sUArJyME07EGoBp/n5JXcwy//G280QvASQzujICMgJNwN1gnAAEIwP/ugHJarKq18lk114BcA/77q1LrZAkAAhCA2edrrgG5Bsw2VVQPgAAsApO9MAABmG2qqB4AAVgEJnthAAIw21RRPQACsAhM8sJMxxo2VLmnV+eNcn6WOYK/lU8a5mZidW626CsOwKJ2jS/MCMgIaBLy4gAEoCfITAMQgCYhLw5AAHqCzDQAAWgS8uIABKAnyEwDEIAmIS8OQAB6gsw0AAFoEvLiAASgJ8hMAxCAJiEvzqs5vP7VmebVHCPd5s0Iu81QZtBUOal//CpuKFBqYMNnmygzWwDongOYkDroIABdTEoegABU3KRlAAjANExKIQACUHGTlgEgANMwKYUACEDFTVoGgABMw6QUAiAAFTdpGQACMA2TUgiAAFTcpGVufBJR/RV+NnZuFiYiOkcPR+fYPUW57s+/RPfWr0WZauHVuZnijLIuZZ+qDZP61zkVnVNPFO/XaKBx/67V2hvCU9cBAE7dIWvXBgOwXcdz6vbmL8CxvC+y+LnWAAAAAElFTkSuQmCC</thumbnail><stage name="Stage" width="480" height="360" costume="0" color="255,255,255,1" tempo="60" threadsafe="false" volume="100" pan="0" lines="flat" ternary="true" codify="false" inheritance="false" sublistIDs="false" scheduled="false" 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= stage.parentThatIsA(IDE_Morph),&#xD;        world = stage.parentThatIsA(WorldMorph);&#xD;&#xD;if (tf != !!tf) return;&#xD;&#xD;try{&#xD;ide.savingPreferences = false;&#xD;&#xD;switch (which) {&#xD;    case &apos;Presentation mode&apos;:&#xD;        if (tf != ide.isAppMode) ide.toggleAppMode();&#xD;        break;&#xD;    case &apos;Retina display support&apos;:&#xD;        if (tf != isRetinaEnabled()) ide.toggleRetina();&#xD;        break;&#xD;    case &apos;Long form input dialog&apos;:&#xD;        if (tf != InputSlotDialogMorph.prototype.isLaunchingExpanded)&#xD;            ide.toggleLongFormInputDialog();&#xD;        break;&#xD;    case &apos;Plain prototype labels&apos;:&#xD;        if (tf != BlockLabelPlaceHolderMorph.prototype.plainLabel)&#xD;            ide.togglePlainPrototypeLabels();&#xD;        break;&#xD;    case &apos;Input sliders&apos;:&#xD;        MorphicPreferences.useSliderForInput = tf;&#xD;        break;&#xD;    case &apos;Execute on slider change&apos;:&#xD;       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