<snapdata remixID="8927207"><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 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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 var="tf"/></list></block></script></block-definition><block-definition 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