ScratchBlocks---init

    const soundColors = ScratchBlocks.Colours.sounds;

    const looksColors = ScratchBlocks.Colours.looks;

    const motionColors = ScratchBlocks.Colours.motion;

    const sensingColors = ScratchBlocks.Colours.sensing;

    const controlColors = ScratchBlocks.Colours.control;

    const eventColors = ScratchBlocks.Colours.event;

    ScratchBlocks.Blocks.sound_sounds_menu.init = function () {
        const json = jsonForMenuBlock('SOUND_MENU', soundsMenu, soundColors, []);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.looks_costume.init = function () {
        const json = jsonForMenuBlock('COSTUME', costumesMenu, looksColors, []);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.looks_backdrops.init = function () {
        const json = jsonForMenuBlock('BACKDROP', backdropsMenu, looksColors, []);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.event_whenbackdropswitchesto.init = function () {
        const json = jsonForHatBlockMenu(
            ScratchBlocks.Msg.EVENT_WHENBACKDROPSWITCHESTO,
            'BACKDROP', backdropNamesMenu, eventColors, []);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.motion_pointtowards_menu.init = function () {
        const mouse = ScratchBlocks.ScratchMsgs.translate('MOTION_POINTTOWARDS_POINTER', 'mouse-pointer');
        const json = jsonForMenuBlock('TOWARDS', spriteMenu, motionColors, [
            [mouse, '_mouse_']
        ]);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.motion_goto_menu.init = function () {
        const random = ScratchBlocks.ScratchMsgs.translate('MOTION_GOTO_RANDOM', 'random position');
        const mouse = ScratchBlocks.ScratchMsgs.translate('MOTION_GOTO_POINTER', 'mouse-pointer');
        const json = jsonForMenuBlock('TO', spriteMenu, motionColors, [
            [random, '_random_'],
            [mouse, '_mouse_']
        ]);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.motion_glideto_menu.init = function () {
        const random = ScratchBlocks.ScratchMsgs.translate('MOTION_GLIDETO_RANDOM', 'random position');
        const mouse = ScratchBlocks.ScratchMsgs.translate('MOTION_GLIDETO_POINTER', 'mouse-pointer');
        const json = jsonForMenuBlock('TO', spriteMenu, motionColors, [
            [random, '_random_'],
            [mouse, '_mouse_']
        ]);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.sensing_of_object_menu.init = function () {
        const stage = ScratchBlocks.ScratchMsgs.translate('SENSING_OF_STAGE', 'Stage');
        const json = jsonForMenuBlock('OBJECT', spriteMenu, sensingColors, [
            [stage, '_stage_']
        ]);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.sensing_of.init = function () {
        const blockId = this.id;
        // Function that fills in menu for the first input in the sensing block.
        // Called every time it opens since it depends on the values in the other block input.
        const menuFn = function () {
            const stageOptions = [
                [ScratchBlocks.Msg.SENSING_OF_BACKDROPNUMBER, 'backdrop #'],
                [ScratchBlocks.Msg.SENSING_OF_BACKDROPNAME, 'backdrop name'],
                [ScratchBlocks.Msg.SENSING_OF_VOLUME, 'volume']
            ];
            const spriteOptions = [
                [ScratchBlocks.Msg.SENSING_OF_XPOSITION, 'x position'],
                [ScratchBlocks.Msg.SENSING_OF_YPOSITION, 'y position'],
                [ScratchBlocks.Msg.SENSING_OF_DIRECTION, 'direction'],
                [ScratchBlocks.Msg.SENSING_OF_COSTUMENUMBER, 'costume #'],
                [ScratchBlocks.Msg.SENSING_OF_COSTUMENAME, 'costume name'],
                [ScratchBlocks.Msg.SENSING_OF_SIZE, 'size'],
                [ScratchBlocks.Msg.SENSING_OF_VOLUME, 'volume']
            ];
            if (vm.editingTarget) {
                let lookupBlocks = vm.editingTarget.blocks;
                let sensingOfBlock = lookupBlocks.getBlock(blockId);

                // The block doesn't exist, but should be in the flyout. Look there.
                if (!sensingOfBlock) {
                    sensingOfBlock = vm.runtime.flyoutBlocks.getBlock(blockId);
                    // If we still don't have a block, just return an empty list . This happens during
                    // scratch blocks construction.
                    if (!sensingOfBlock) {
                        return [['', '']];
                    }
                    // The block was in the flyout so look up future block info there.
                    lookupBlocks = vm.runtime.flyoutBlocks;
                }
                const sort = function (options) {
                    options.sort(ScratchBlocks.scratchBlocksUtils.compareStrings);
                };
                // Get all the stage variables (no lists) so we can add them to menu when the stage is selected.
                const stageVariableOptions = vm.runtime.getTargetForStage().getAllVariableNamesInScopeByType('');
                sort(stageVariableOptions);
                const stageVariableMenuItems = stageVariableOptions.map(variable => [variable, variable]);
                if (sensingOfBlock.inputs.OBJECT.shadow !== sensingOfBlock.inputs.OBJECT.block) {
                    // There's a block dropped on top of the menu. It'd be nice to evaluate it and
                    // return the correct list, but that is tricky. Scratch2 just returns stage options
                    // so just do that here too.
                    return stageOptions.concat(stageVariableMenuItems);
                }
                const menuBlock = lookupBlocks.getBlock(sensingOfBlock.inputs.OBJECT.shadow);
                const selectedItem = menuBlock.fields.OBJECT.value;
                if (selectedItem === '_stage_') {
                    return stageOptions.concat(stageVariableMenuItems);
                }
                // Get all the local variables (no lists) and add them to the menu.
                const target = vm.runtime.getSpriteTargetByName(selectedItem);
                let spriteVariableOptions = [];
                // The target should exist, but there are ways for it not to (e.g. #4203).
                if (target) {
                    spriteVariableOptions = target.getAllVariableNamesInScopeByType('', true);
                    sort(spriteVariableOptions);
                }
                const spriteVariableMenuItems = spriteVariableOptions.map(variable => [variable, variable]);
                return spriteOptions.concat(spriteVariableMenuItems);
            }
            return [['', '']];
        };

        const json = jsonForSensingMenus(menuFn);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.sensing_distancetomenu.init = function () {
        const mouse = ScratchBlocks.ScratchMsgs.translate('SENSING_DISTANCETO_POINTER', 'mouse-pointer');
        const json = jsonForMenuBlock('DISTANCETOMENU', spriteMenu, sensingColors, [
            [mouse, '_mouse_']
        ]);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.sensing_touchingobjectmenu.init = function () {
        const mouse = ScratchBlocks.ScratchMsgs.translate('SENSING_TOUCHINGOBJECT_POINTER', 'mouse-pointer');
        const edge = ScratchBlocks.ScratchMsgs.translate('SENSING_TOUCHINGOBJECT_EDGE', 'edge');
        const json = jsonForMenuBlock('TOUCHINGOBJECTMENU', spriteMenu, sensingColors, [
            [mouse, '_mouse_'],
            [edge, '_edge_']
        ]);
        this.jsonInit(json);
    };

    ScratchBlocks.Blocks.control_create_clone_of_menu.init = function () {
        const json = jsonForMenuBlock('CLONE_OPTION', cloneMenu, controlColors, []);
        this.jsonInit(json);
    };

    ScratchBlocks.VerticalFlyout.getCheckboxState = function (blockId) {
        const monitoredBlock = vm.runtime.monitorBlocks._blocks[blockId];
        return monitoredBlock ? monitoredBlock.isMonitored : false;
    };

    ScratchBlocks.FlyoutExtensionCategoryHeader.getExtensionState = function (extensionId) {
        if (vm.getPeripheralIsConnected(extensionId)) {
            return ScratchBlocks.StatusButtonState.READY;
        }
        return ScratchBlocks.StatusButtonState.NOT_READY;
    };

    ScratchBlocks.FieldNote.playNote_ = function (noteNum, extensionId) {
        vm.runtime.emit('PLAY_NOTE', noteNum, extensionId);
    };

    // Use a collator's compare instead of localeCompare which internally
    // creates a collator. Using this is a lot faster in browsers that create a
    // collator for every localeCompare call.
    const collator = new Intl.Collator([], {
        sensitivity: 'base',
        numeric: true
    });
    ScratchBlocks.scratchBlocksUtils.compareStrings = function (str1, str2) {
        return collator.compare(str1, str2);
    };

    // Blocks wants to know if 3D CSS transforms are supported. The cross
    // section of browsers Scratch supports and browsers that support 3D CSS
    // transforms will make the return always true.
    //
    // Shortcutting to true lets us skip an expensive style recalculation when
    // first loading the Scratch editor.
    ScratchBlocks.utils.is3dSupported = function () {
        return true;
    };