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</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="175" y="140" 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="10" y="24"><block s="receiveKey"><l><option>space</option></l></block><custom-block s="Draw Checkerboard with %n Rows"><l>8</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 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