<snapdata remixID="8923458"><project name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" version="1"><notes></notes><thumbnail>data:image/png;base64,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</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" id="1"><pentrails>data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAeAAAAFoCAYAAACPNyggAAAb6klEQVR4Xu3XsYpd15qFURnaYEfKHVzlDtpPKLigJ/QNlOsGyh3Z4AY1OC/0Ff+kThWMiid7HcZe7I/64Z0/AgQIECBA4MUFfnjxEx1IgAABAgQIvBNgl4AAAQIECDxAQIAfgO5IAgQIECAgwO4AAQIECBB4gIAAPwDdkQQIECBAQIDdAQIECBAg8AABAX4AuiMJECBAgIAAuwMECBAgQOABAgL8AHRHEiBAgAABAXYHCBAgQIDAAwQE+AHojiRAgAABAgLsDhAgQIAAgQcICPAD0B1JgAABAgQE2B0gQIAAAQIPEBDgB6A7kgABAgQICLA7QIAAAQIEHiAgwA9AdyQBAgQIEBBgd4AAAQIECDxAQIAfgO5IAgQIECAgwO4AAQIECBB4gIAAPwDdkQQIECBAQIDdAQIECBAg8AABAX4AuiMJECBAgIAAuwMECBAgQOABAgL8AHRHEiBAgAABAXYHCBAgQIDAAwQE+AHojiRAgAABAgLsDhAgQIAAgQcICPAD0B1JgAABAgQE2B0gQIAAAQIPEBDgB6A7kgABAgQICLA7QIAAAQIEHiAgwA9AdyQBAgQIEBBgd4AAAQIECDxAQIAfgO5IAgQIECAgwO4AAQIECBB4gIAAPwDdkQQIECBAQIDdAQIECBAg8AABAX4AuiMJECBAgIAAuwMECBAgQOABAgL8AHRHEiBAgAABAXYHCBAgQIDAAwQE+AHojiRAgAABAgLsDhAgQIAAgQcICPAD0B1JgAABAgQE2B0gQIAAAQIPEBDgB6A7kgABAgQICLA7QIAAAQIEHiAgwA9AdyQBAgQIEBBgd4AAAQIECDxAQIAfgO5IAgQIECAgwC90B77977/+/UJH5WN+/vzfvH2p4Z+//uuljsrncGpUnN6u01//9+7VfZ+a5tteCfALvb9vv3349kJH5WN+/vwlb19q+OevH17qqHwOp0bF6e06/fX3Oy1or2+6gj7lfPphAtygBZhTE2gr96k5CXBzWq8EeC36xPMEuEH7YHJqAm3lPjUnAW5O65UAr0UF+CTqg9n4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC16BPP+/TL+28vdJRjCBAg8CyBj1//0IJniW3G0DeO333KTz++e3UB9l/Ud1/bPwNOnJpAW73G+/TD71+0oL2+6Qr6lPPphwlwg/7585c2fMHVa/xgcmoXgFNzEuDmtF4J8Fr0iecJcIP2weTUBNrKfWpOAtyc1isBXosK8EnUB7PxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBr0See9+mX999e6CjHECBA4FkCH7/+oQXPEtuMoW8cv/uUb799eHUB9l/Ud1/bPwNOnJpAW73G+/TX3++0oL2+6Qr6lPPphwlwg/7z1w9t+IKr1/jB5NQuAKfmJMDNab0S4LXoE88T4Abtg8mpCbSV+9ScBLg5rVcCvBYV4JOoD2bj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXok8879Mv77+90FGOIUCAwLMEPn79QwueJbYZQ984fvcpP/347tUF2H9R331t/ww4cWoCbfUa79MPv3/Rgvb6pivoU86nHybADfrnz1/a8AVXr/GDyaldAE7NSYCb03olwGvRJ54nwA3aB5NTE2gr96k5CXBzWq8EeC0qwCdRH8zGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRZ943qdf3n97oaMcQ4AAgWcJfPz6hxY8S2wzhr5x/O5Tvv324dUF2H9R331t/ww4cWoCbfUa79Nff7/Tgvb6pivoU86nHybADfrPXz+04QuuXuMHk1O7AJyakwA3p/VKgNeiTzxPgBu0DyanJtBW7lNzEuDmtF4J8FpUgE+iPpiNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiz7xvE+/vP/2Qkc5hgABAs8S+Pj1Dy14lthmDH3j+N2n/PTju1cXYP9Fffe1/TPgxKkJtNVrvE8//P5FC9rrm66gTzmffpgAN+ifP39pwxdcvcYPJqd2ATg1JwFuTuuVAK9Fn3ieADdoH0xOTaCt3KfmJMDNab0S4LWoAJ9EfTAbHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8Fn3ieZ9+ef/thY5yDAECBJ4l8PHrH1rwLLHNGPrG8btP+fbbh1cXYP9Fffe1/TPgxKkJtNVrvE9//f1OC9rrm66gTzmffpgAN+g/f/3Qhi+4eo0fTE7tAnBqTgLcnNYrAV6LPvE8AW7QPpicmkBbuU/NSYCb03olwGtRAT6J+mA2Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LfrE8z798v7bCx3lGAIECDxL4OPXP7TgWWKbMfSN43ef8tOP715dgP0X9d3X9s+AE6cm0Fav8T798PsXLWivb7qCPuV8+mEC3KB//vylDV9w9Ro/mJzaBeDUnAS4Oa1XArwWfeJ5AtygfTA5NYG2cp+akwA3p/VKgNeiAnwS9cFsfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWlSAT6LC0vg4cWoCbSXAzWm9EuC1qACfRIWl8XHi1ATaSoCb03olwGtRAT6JCkvj48SpCbSVADen9UqA16ICfBIVlsbHiVMTaCsBbk7rlQCvRQX4JCosjY8TpybQVgLcnNYrAV6LCvBJVFgaHydOTaCtBLg5rVcCvBYV4JOosDQ+TpyaQFsJcHNarwR4LSrAJ1FhaXycODWBthLg5rReCfBaVIBPosLS+DhxagJtJcDNab0S4LWoAJ9EhaXxceLUBNpKgJvTeiXAa1EBPokKS+PjxKkJtJUAN6f1SoDXogJ8EhWWxseJUxNoKwFuTuuVAK9FBfgkKiyNjxOnJtBWAtyc1isBXosK8ElUWBofJ05NoK0EuDmtVwK8FhXgk6iwND5OnJpAWwlwc1qvBHgtKsAnUWFpfJw4NYG2EuDmtF4J8FpUgE+iwtL4OHFqAm0lwM1pvRLgtagAn0SFpfFx4tQE2kqAm9N6JcBrUQE+iQpL4+PEqQm0lQA3p/VKgNeiAnwSFZbGx4lTE2grAW5O65UAr0UF+CQqLI2PE6cm0FYC3JzWKwFeiwrwSVRYGh8nTk2grQS4Oa1XArwWFeCTqLA0Pk6cmkBbCXBzWq8EeC0qwCdRYWl8nDg1gbYS4Oa0XgnwWvSpAP/Pu3+/0FH5mD9//VfevtTw58//famj8jmcGhWnt+v0w3/+++q+T03zba8E+G2/P7+eAAECBN6ogAC/0RfnZxMgQIDA2xYQ4Lf9/vx6AgQIEHijAgL8Rl+cn02AAAECb1tAgN/2+/PrCRAgQOCNCgjwG31xfjYBAgQIvG0BAX7b78+vJ0CAAIE3KiDAb/TF+dkECBAg8LYFBPhtvz+/ngABAgTeqIAAv9EX52cTIECAwNsWEOC3/f78egIECBB4owL/D1Ve+kpVzIenAAAAAElFTkSuQmCC</pentrails><costumes><list struct="atomic" id="2"></list></costumes><sounds><list struct="atomic" id="3"></list></sounds><variables></variables><blocks></blocks><scripts></scripts><sprites><sprite name="Sprite" idx="1" x="-150" y="146" heading="90" scale="1" volume="100" pan="0" rotation="1" draggable="true" costume="0" color="8,5,0,1" pen="tip" id="8"><costumes><list struct="atomic" id="9"></list></costumes><sounds><list struct="atomic" id="10"></list></sounds><blocks></blocks><variables></variables><scripts><script x="105" y="119"><custom-block s="Draw Checkerboard Size of squares; %s Starter Cord X; %s Starter Cord Y; %s"><l>37</l><l>-150</l><l>-150</l></custom-block></script></scripts></sprite></sprites></stage><hidden></hidden><headers></headers><code></code><blocks><block-definition s="set flag %&apos;which&apos; to %&apos;tf&apos;" type="command" category="sensing"><header></header><code></code><translations></translations><inputs><input type="%s" readonly="true"><options>Presentation mode&#xD;Retina display support&#xD;Long form input dialog&#xD;Plain prototype labels&#xD;Input sliders&#xD;Execute on slider change&#xD;Clicking sound&#xD;Turbo mode&#xD;Flat design&#xD;Keyboard editing&#xD;Table support&#xD;Table lines&#xD;Visible stepping&#xD;Thread safe scripts&#xD;Prefer smooth animations&#xD;Flat line ends&#xD;Codification support&#xD;Inheritance support</options></input><input type="%b"></input></inputs><script><block s="doRun"><block s="reportJSFunction"><list><l>which</l><l>tf</l></list><l>var   stage = this.parentThatIsA(StageMorph),&#xD;        ide = 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;        ArgMorph.prototype.executeOnSliderEdit = tf;&#xD;        break;&#xD;    case &apos;Clicking sound&apos;:&#xD;        if (tf != !!BlockMorph.prototype.snapSound)&#xD;            BlockMorph.prototype.toggleSnapSound();&#xD;        break;&#xD;    case &apos;Turbo mode&apos;:&#xD;        if (tf != stage.isFastTracked)&#xD;            ide.toggleFastTracking();&#xD;        break;&#xD;    case &apos;Flat design&apos;:&#xD;        if (tf == MorphicPreferences.isFlat) break;&#xD;        if (tf)&#xD;            ide.flatDesign();&#xD;        else&#xD;            ide.defaultDesign();&#xD;        break;&#xD;    case &apos;Keyboard editing&apos;:&#xD;            ScriptsMorph.prototype.enableKeyboard = tf;&#xD;        break;&#xD;    case &apos;Table support&apos;:&#xD;            List.prototype.enableTables = tf;&#xD;        break;&#xD;    case &apos;Table lines&apos;:&#xD;                TableMorph.prototype.highContrast = tf;&#xD;        break;&#xD;    case &apos;Visible stepping&apos;:&#xD;        if (tf != Process.prototype.enableSingleStepping)&#xD;            ide.toggleSingleStepping();&#xD;        break;&#xD;    case &apos;Thread safe scripts&apos;:&#xD;        stage.isThreadSafe = tf;&#xD;        break;&#xD;    case &apos;Prefer smooth animations&apos;:&#xD;        if (tf != (StageMorph.prototype.frameRate &gt; 0))&#xD;            ide.toggleVariableFrameRate();&#xD;        break;&#xD;    case &apos;Flat line ends&apos;:&#xD;        SpriteMorph.prototype.useFlatLineEnds = tf;&#xD;        break;&#xD;    case &apos;Codification support&apos;:&#xD;        if (tf != StageMorph.prototype.enableCodeMapping) {&#xD;            StageMorph.prototype.enableCodeMapping = tf;&#xD;            ide.currentSprite.blocksCache.variables = null;&#xD;            ide.currentSprite.paletteCache.variables = null;&#xD;            ide.refreshPalette();&#xD;        }&#xD;        break;&#xD;    case &apos;Inheritance support&apos;:&#xD;        if (tf != StageMorph.prototype.enableInheritance) {&#xD;            StageMorph.prototype.enableInheritance = tf;&#xD;            ide.currentSprite.blocksCache.variables = null;&#xD;            ide.currentSprite.paletteCache.variables = null;&#xD;            ide.refreshPalette();&#xD;        }&#xD;        break;&#xD;};&#xD;}&#xD;finally {&#xD;ide.savingPreferences = false;&#xD;};&#xD;</l></block><list><block var="which"/><block 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