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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><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"/><sprite name="Sprite" idx="1" x="-187" y="134" heading="270" scale="1" volume="100" pan="0" rotation="1" draggable="true" costume="0" color="255,47,31,1" pen="tip" id="10"><costumes><list struct="atomic" id="11"></list></costumes><sounds><list struct="atomic" id="12"></list></sounds><blocks></blocks><variables></variables><scripts><script x="346" y="32"><custom-block s="draw checkerboard"></custom-block></script><script x="192" y="177"><block s="turnLeft"><l>180</l></block><block s="gotoXY"><l>-187</l><l>-146</l></block><block s="clear"></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;            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