<snapdata remixID="9046298"><project name="U2L4-checkerboard" 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,iVBORw0KGgoAAAANSUhEUgAAAeAAAAFoCAYAAACPNyggAAAZXklEQVR4Xu3VsU0rQRhG0dkACVexuRP6L4PEuaswEsE+0cJeLTN6HPLPFse/5m7DHwECBAgQIPDrAtuvf6MvJECAAAECBIYAOwICBAgQIDBBQIAnoPtKAgQIECAgwG6AAAECBAhMEBDgCei+kgABAgQICLAbIECAAAECEwQEeAK6ryRAgAABAgLsBggQIECAwAQBAZ6A7isJECBAgIAAuwECBAgQIDBBQIAnoPtKAgQIECAgwG6AAAECBAhMEBDgCei+kgABAgQICLAbIECAAAECEwQEeAK6ryRAgAABAgLsBggQIECAwAQBAZ6A7isJECBAgIAAuwECBAgQIDBBQIAnoPtKAgQIECAgwG6AAAECBAhMEBDgCei+kgABAgQICLAbIECAAAECEwQEeAK6ryRAgAABAgLsBggQIECAwAQBAZ6A7isJECBAgIAAuwECBAgQIDBBQIAnoPtKAgQIECAgwG6AAAECBAhMEBDgCei+kgABAgQICHC8gfe3ccSPuHT+uu+Xfn798NvjWT/i0j2/xsvv//bbPp8aEn5ieAHvZyrADVCA+TWBtnZ/zU+Ao1+bWwtwuwEPIL8m0Nbur/kJcPRrc2sBbjfgAeTXBNra/TU/AY5+bW4twO0GPID8mkBbu7/mJ8DRr82tBbjdgAeQXxNoa/fX/AQ4+rW5tQC3G/AA8msCbe3+mp8AR782txbgdgMeQH5NoK3dX/MT4OjX5tYC3G7AA8ivCbS1+2t+Ahz92txagNsNeAD5NYG2dn/NT4CjX5tbC3C7AQ8gvybQ1u6v+Qlw9GtzawFuN+AB5NcE2tr9NT8Bjn5tbi3A7QY8gPyaQFu7v+YnwNGvza0FuN2AB5BfE2hr99f8BDj6tbm1ALcb8ADyawJt7f6anwBHvza3FuB2Ax5Afk2grd1f8xPg6Nfm1gLcbsADyK8JtLX7a34CHP3a3FqA2w14APk1gbZ2f81PgKNfm1sLcLsBDyC/JtDW7q/5CXD0a3NrAW434AHk1wTa2v01PwGOfm1uLcDtBjyA/JpAW7u/5ifA0a/NrQW43YAHkF8TaGv31/wEOPq1ubUAtxvwAPJrAm3t/pqfAEe/NrcW4HYDHkB+TaCt3V/zE+Do1+bWAtxuwAPIrwm0tftrfgIc/drcWoDbDXgA+TWBtnZ/zU+Ao1+bWwtwuwEPIL8m0Nbur/kJcPRrc2sBbjfgAeTXBNra/TU/AY5+bW4twO0GPID8mkBbu7/mJ8DRr82tBbjdgAeQXxNoa/fX/AQ4+rW5tQC3G/AA8msCbe3+mp8AR782txbgdgMeQH5NoK3dX/MT4OjX5tYC3G7AA8ivCbS1+2t+Ahz92txagNsNeAD5NYG2dn/NT4CjX5tbC3C7AQ8gvybQ1u6v+Qlw9GtzawFuN+AB5NcE2tr9NT8Bjn5tbi3A7QY8gPyaQFu7v+YnwNGvza0FuN2AB5BfE2hr99f8BDj6tbm1ALcb8ADyawJt7f6anwBHvza3FuB2Ax5Afk2grd1f8xPg6Nfm1sfHfqys4IFpvw4/fk2grVe/v6/vsbX/8G+v4cXfX4Ab4Ou+tw+4eL36A8ivHQC/5ifAzU+Am98Q4AboAeTXBNra/TU/AW5+Atz8BDj6eQAbID9+TaCtBbj5CXDzE+DoJyANkB+/JtDWAtz8BLj5CXD0E5AGyI9fE2hrAW5+Atz8BDj6CUgD5MevCbS1ADc/AW5+Ahz9BKQB8uPXBNpagJufADc/AY5+AtIA+fFrAm0twM1PgJufAEc/AWmA/Pg1gbYW4OYnwM1PgKOfgDRAfvyaQFsLcPMT4OYnwNFPQBogP35NoK0FuPkJcPMT4OgnIA2QH78m0NYC3PwEuPkJcPQTkAbIj18TaGsBbn4C3PwEOPoJSAPkx68JtLUANz8Bbn4CHP0EpAHy49cE2lqAm58ANz8Bjn4C0gD58WsCbS3AzU+Am58ARz8BaYD8+DWBthbg5ifAzU+Ao5+ANEB+/JpAWwtw8xPg5ifA0U9AGiA/fk2grQW4+Qlw8xPg6CcgDZAfvybQ1gLc/AS4+Qlw9BOQBsiPXxNoawFufgLc/AQ4+glIA+THrwm0tQA3PwFufgIc/QSkAfLj1wTaWoCbnwA3PwGOfgLSAPnxawJtLcDNT4CbnwBHPwFpgPz4NYG2FuDmJ8DNT4Cjn4A0QH78mkBbC3DzE+DmJ8DRT0AaID9+TaCtBbj5CXDzE+DoJyANkB+/JtDWAtz8BLj5CXD0E5AGyI9fE2hrAW5+Atz8BDj6CUgD5MevCbS1ADc/AW5+Ahz9BKQB8uPXBNpagJufADc/AY5+AtIA+fFrAm0twM1PgJufAEc/AWmA/Pg1gbYW4OYnwM1PgKOfgDRAfvyaQFsLcPMT4OYnwNFPQBogP35NoK0FuPkJcPMT4OgnIA2QH78m0NYC3PwEuPkJcPQTkAbIj18TaGsBbn4C3PwEOPoJSAPkx68JtLUANz8Bbn4CHP0EpAHy49cE2lqAm58AN7/x/jaO+BGXzj3QjZcfvybQ1qvf3/b51JDwE8MLeD9TAW6At8ezfcDF69UfQH7tAPg1PwGOfm1uLcDtBjyA/JpAW7u/5ifA0a/NrQW43YAHkF8TaGv31/wEOPq1ubUAtxvwAPJrAm3t/pqfAEe/NrcW4HYDHkB+TaCt3V/zE+Do1+bWAtxuwAPIrwm0tftrfgIc/drcWoDbDXgA+TWBtnZ/zU+Ao1+bWwtwuwEPIL8m0Nbur/kJcPRrc2sBbjfgAeTXBNra/TU/AY5+bW4twO0GPID8mkBbu7/mJ8DRr82tBbjdgAeQXxNoa/fX/AQ4+rW5tQC3G/AA8msCbe3+mp8AR782txbgdgMeQH5NoK3dX/MT4OjX5tYC3G7AA8ivCbS1+2t+Ahz92txagNsNeAD5NYG2dn/NT4CjX5tbC3C7AQ8gvybQ1u6v+Qlw9GtzawFuN+AB5NcE2tr9NT8Bjn5tbi3A7QY8gPyaQFu7v+YnwNGvza0FuN2AB5BfE2hr99f8BDj6tbm1ALcb8ADyawJt7f6anwBHvza3FuB2Ax5Afk2grd1f8xPg6Nfm1gLcbsADyK8JtLX7a34CHP3a3FqA2w14APk1gbZ2f81PgKNfm1sLcLsBDyC/JtDW7q/5CXD0a3NrAW434AHk1wTa2v01PwGOfm1uLcDtBjyA/JpAW7u/5ifA0a/NrQW43YAHkF8TaGv31/wEOPq1ubUAtxvwAPJrAm3t/pqfAEe/NrcW4HYDHkB+TaCt3V/zE+Do1+bWAtxuwAPIrwm0tftrfgIc/drcWoDbDXgA+TWBtnZ/zU+Ao1+bWwtwuwEPIL8m0Nbur/kJcPRrc2sBbjfgAeTXBNra/TU/AY5+bW4twO0GPID8mkBbu7/mJ8DRr82tBbjdgAeQXxNoa/fX/AQ4+rW5tQC3G/AA8msCbe3+mp8AR782txbgdgMeQH5NoK3dX/MT4OjX5tYC3G7AA8ivCbS1+2t+Ahz92txagNsNeAD5NYG2dn/NT4CjX5tbHx/7sbKCB6b9Ovz4NYG2Xv3+vr7H1v7Dv72GF39/AW6Ar/vePuDi9eoPIL92APyanwA3PwFufkOAG6AHkF8TaGv31/wEuPkJcPMT4OjnAWyA/Pg1gbYW4OYnwM1PgKOfgDRAfvyaQFsLcPMT4OYnwNFPQBogP35NoK0FuPkJcPMT4OgnIA2QH78m0NYC3PwEuPkJcPQTkAbIj18TaGsBbn4C3PwEOPoJSAPkx68JtLUANz8Bbn4CHP0EpAHy49cE2lqAm58ANz8Bjn4C0gD58WsCbS3AzU+Am58ARz8BaYD8+DWBthbg5ifAzU+Ao5+ANEB+/JpAWwtw8xPg5ifA0U9AGiA/fk2grQW4+Qlw8xPg6CcgDZAfvybQ1gLc/AS4+Qlw9BOQBsiPXxNoawFufgLc/AQ4+glIA+THrwm0tQA3PwFufgIc/QSkAfLj1wTaWoCbnwA3PwGOfgLSAPnxawJtLcDNT4CbnwBHPwFpgPz4NYG2FuDmJ8DNT4Cjn4A0QH78mkBbC3DzE+DmJ8DRT0AaID9+TaCtBbj5CXDzE+DoJyANkB+/JtDWAtz8BLj5CXD0E5AGyI9fE2hrAW5+Atz8BDj6CUgD5MevCbS1ADc/AW5+Ahz9BKQB8uPXBNpagJufADc/AY5+AtIA+fFrAm0twM1PgJufAEc/AWmA/Pg1gbYW4OYnwM1PgKOfgDRAfvyaQFsLcPMT4OYnwNFPQBogP35NoK0FuPkJcPMT4OgnIA2QH78m0NYC3PwEuPkJcPQTkAbIj18TaGsBbn4C3PwEOPoJSAPkx68JtLUANz8Bbn4CHP0EpAHy49cE2lqAm58ANz8Bjn4C0gD58WsCbS3AzU+Am58ARz8BaYD8+DWBthbg5ifAzU+Ao5+ANEB+/JpAWwtw8xPg5ifA0U9AGiA/fk2grQW4+Qlw8xPg6CcgDZAfvybQ1gLc/AS4+Qlw9BOQBsiPXxNoawFufgLc/Mb72zjiR1w690A3Xn78mkBbr35/2+dTQ8JPDC/g/UwFuAHeHs/2ARevV38A+bUD4Nf8BDj6tbm1ALcb8ADyawJt7f6anwBHvza3FuB2Ax5Afk2grd1f8xPg6Nfm1gLcbsADyK8JtLX7a34CHP3a3FqA2w14APk1gbZ2f81PgKNfm1sLcLsBDyC/JtDW7q/5CXD0a3NrAW434AHk1wTa2v01PwGOfm1uLcDtBjyA/JpAW7u/5ifA0a/NrQW43YAHkF8TaGv31/wEOPq1ubUAtxvwAPJrAm3t/pqfAEe/NrcW4HYDHkB+TaCt3V/zE+Do1+bWAtxuwAPIrwm0tftrfgIc/drcWoDbDXgA+TWBtnZ/zU+Ao1+bWwtwuwEPIL8m0Nbur/kJcPRrc2sBbjfgAeTXBNra/TU/AY5+bW4twO0GPID8mkBbu7/mJ8DRr82tBbjdgAeQXxNoa/fX/AQ4+rW5tQC3G/AA8msCbe3+mp8AR782txbgdgMeQH5NoK3dX/MT4OjX5tYC3G7AA8ivCbS1+2t+Ahz92txagNsNeAD5NYG2dn/NT4CjX5tbC3C7AQ8gvybQ1u6v+Qlw9GtzawFuN+AB5NcE2tr9NT8Bjn5tbi3A7QY8gPyaQFu7v+YnwNGvza0FuN2AB5BfE2hr99f8BDj6tbm1ALcb8ADyawJt7f6anwBHvza3FuB2Ax5Afk2grd1f8xPg6Nfm1gLcbsADyK8JtLX7a34CHP3a3FqA2w14APk1gbZ2f81PgKNfm1sLcLsBDyC/JtDW7q/5CXD0a3NrAW434AHk1wTa2v01PwGOfm1uLcDtBjyA/JpAW7u/5ifA0a/NrQW43YAHkF8TaGv31/wEOPq1ubUAtxvwAPJrAm3t/pqfAEe/NrcW4HYDHkB+TaCt3V/zE+Do1+bWAtxuwAPIrwm0tftrfgIc/drcWoDbDXgA+TWBtnZ/zU+Ao1+bWwtwuwEPIL8m0Nbur/kJcPRrc2sBbjfgAeTXBNra/TU/AY5+bW59fOzHygoemPbr8OPXBNp69fv7+h5b+w//9hpe/P0FuAG+7nv7gIvXqz+A/NoB8Gt+Atz8BLj5DQFugB5Afk2grd1f8xPg5ifAzU+Ao58HsAHy49cE2lqAm58ANz8Bjn4C0gD58WsCbS3AzU+Am58ARz8BaYD8+DWBthbg5ifAzU+Ao5+ANEB+/JpAWwtw8xPg5ifA0U9AGiA/fk2grQW4+Qlw8xPg6CcgDZAfvybQ1gLc/AS4+Qlw9BOQBsiPXxNoawFufgLc/AQ4+glIA+THrwm0tQA3PwFufgIc/QSkAfLj1wTaWoCbnwA3PwGOfgLSAPnxawJtLcDNT4CbnwBHPwFpgPz4NYG2FuDmJ8DNT4Cjn4A0QH78mkBbC3DzE+DmJ8DRT0AaID9+TaCtBbj5CXDzE+DoJyANkB+/JtDWAtz8BLj5CXD0E5AGyI9fE2hrAW5+Atz8BDj6CUgD5MevCbS1ADc/AW5+Ahz9BKQB8uPXBNpagJufADc/AY5+AtIA+fFrAm0twM1PgJufAEc/AWmA/Pg1gbYW4OYnwM1PgKOfgDRAfvyaQFsLcPMT4OYnwNFPQBogP35NoK0FuPkJcPMT4OgnIA2QH78m0NYC3PwEuPkJcPQTkAbIj18TaGsBbn4C3PwEOPoJSAPkx68JtLUANz8Bbn4CHP0EpAHy49cE2lqAm58ANz8Bjn4C0gD58WsCbS3AzU+Am58ARz8BaYD8+DWBthbg5ifAzU+Ao5+ANEB+/JpAWwtw8xPg5ifA0U9AGiA/fk2grQW4+Qlw8xPg6CcgDZAfvybQ1gLc/AS4+Qlw9BOQBsiPXxNoawFufgLc/AQ4+glIA+THrwm0tQA3PwFufgIc/QSkAfLj1wTaWoCbnwA3PwGOfgLSAPnxawJtLcDNT4CbnwBHPwFpgPz4NYG2FuDmJ8DNT4Cjn4A0QH78mkBbC3DzE+DmJ8DRT0AaID9+TaCtBbj5CXDzG+9v44gfcencA914+fFrAm29+v1tn08NCT8xvID3MxXgBnh7PNsHXLxe/QHk1w6AX/MT4OjX5tYC3G7AA8ivCbS1+2t+Ahz92txagNsNeAD5NYG2dn/NT4CjX5tbC3C7AQ8gvybQ1u6v+Qlw9GtzawFuN+AB5NcE2tr9NT8Bjn5tbi3A7QY8gPyaQFu7v+YnwNGvza0FuN2AB5BfE2hr99f8BDj6tbm1ALcb8ADyawJt7f6anwBHvza3FuB2Ax5Afk2grd1f8xPg6Nfm1gLcbsADyK8JtLX7a34CHP3a3FqA2w14APk1gbZ2f81PgKNfm1sLcLsBDyC/JtDW7q/5CXD0a3NrAW434AHk1wTa2v01PwGOfm1uLcDtBjyA/JpAW7u/5ifA0a/NrQW43YAHkF8TaGv31/wEOPq1ubUAtxvwAPJrAm3t/pqfAEe/NrcW4HYDHkB+TaCt3V/zE+Do1+bWAtxuwAPIrwm0tftrfgIc/drcWoDbDXgA+TWBtnZ/zU+Ao1+bWwtwuwEPIL8m0Nbur/kJcPRrc2sBbjfgAeTXBNra/TU/AY5+bW4twO0GPID8mkBbu7/mJ8DRr82tBbjdgAeQXxNoa/fX/AQ4+rW5tQC3G/AA8msCbe3+mp8AR782txbgdgMeQH5NoK3dX/MT4OjX5tYC3G7AA8ivCbS1+2t+Ahz92txagNsNeAD5NYG2dn/NT4CjX5tbC3C7AQ8gvybQ1u6v+Qlw9GtzawFuN+AB5NcE2tr9NT8Bjn5tbi3A7QY8gPyaQFu7v+YnwNGvza0FuN2AB5BfE2hr99f8BDj6tbm1ALcb8ADyawJt7f6anwBHvza3FuB2Ax5Afk2grd1f8xPg6Nfm1gLcbsADyK8JtLX7a34CHP3a3FqA2w14APk1gbZ2f81PgKNfm1sLcLsBDyC/JtDW7q/5CXD0a3NrAW434AHk1wTa2v01PwGOfm1uLcDtBjyA/JpAW7u/5ifA0a/NrQW43YAHkF8TaGv31/wEOPq1ufXxsR8rK3hg2q/Dj18TaOvV7+/re2ztP/zba3jx9xfgBvi67+0DLl6v/gDyawfAr/kJcPMT4OY3BLgBegD5NYG2dn/NT4CbnwA3PwGOfh7ABsiPXxNoawFufgLc/AQ4+glIA+THrwm0tQA3PwFufgIc/QSkAfLj1wTaWoCbnwA3PwGOfgLSAPnxawJtLcDNT4CbnwBHPwFpgPz4NYG2FuDmJ8DNT4Cjn4A0QH78mkBbC3DzE+DmJ8DRT0AaID9+TaCtBbj5CXDzE+DoJyANkB+/JtDWAtz8BLj5CXD0E5AGyI9fE2hrAW5+Atz8BDj6CUgD5MevCbS1ADc/AW5+Ahz9BKQB8uPXBNpagJufADc/AY5+AtIA+fFrAm0twM1PgJufAEc/AWmA/Pg1gbYW4OYnwM1PgKOfgDRAfvyaQFsLcPMT4OYnwNFPQBogP35NoK0FuPkJcPMT4OgnIA2QH78m0NYC3PwEuPkJcPQTkAbIj18TaGsBbn4C3PwEOPoJSAPkx68JtLUANz8Bbn4CHP0EpAHy49cE2lqAm58ANz8Bjn4C0gD58WsCbS3AzU+Am58ARz8BaYD8+DWBthbg5ifAzU+Ao5+ANEB+/JpAWwtw8xPg5ifA0U9AGiA/fk2grQW4+Qlw8xPg6CcgDZAfvybQ1gLc/AS4+Qlw9BOQBsiPXxNoawFufgLc/AQ4+glIA+THrwm0tQA3PwFufgIc/QSkAfLj1wTaWoCbnwA3PwGOfgLSAPnxawJtLcDNT4CbnwBHPwFpgPz4NYG2FuDmJ8DNT4Cjn4A0QH78mkBbC3DzE+DmJ8DRT0AaID9+TaCtBbj5CXDzE+DoJyANkB+/JtDWAtz8BLj5CXD0E5AGyI9fE2hrAW5+Atz8BDj6CUgD5MevCbS1ADc/AW5+Ahz9BKQB8uPXBNpagJufADc/AY5+AtIA+fFrAm0twM1PgJufAEc/AWmA/Pg1gbYW4OYnwM3PmgABAgQInBIQ4FNsRgQIECBAoAkIcPOzJkCAAAECpwQE+BSbEQECBAgQaAIC3PysCRAgQIDAKQEBPsVmRIAAAQIEmoAANz9rAgQIECBwSkCAT7EZESBAgACBJiDAzc+aAAECBAicEhDgU2xGBAgQIECgCfwD5FOCaN5BCR0AAAAASUVORK5CYII=</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="160" y="130" heading="90" scale="1" volume="100" pan="0" rotation="1" draggable="true" costume="0" color="255,47,31,1" 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="23" y="10"><block s="clear"></block></script><script x="80" y="225"><custom-block s="Draw board"></custom-block></script></scripts></sprite><watcher scope="Sprite" s="xPosition" style="normal" x="10" y="10" color="74,108,212" hidden="true"/><watcher scope="Sprite" s="yPosition" style="normal" x="10" y="31.000001999999995" color="74,108,212" hidden="true"/></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;   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