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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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</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="210" y="115" 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="198" y="147"><custom-block s="Make Checker Board"></custom-block></script></scripts></sprite><watcher var="y value" style="normal" x="10" y="10" color="243,118,29"/></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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