Converts selected Grayscale opacity masks to RGB to correct sharp edges due to black depth. Adobe Illustrator script

GrayOpacityMaskFix.jsx

/*
  Converts selected Grayscale opacity masks to RGB to correct sharp edges due to black depth
  Attention: Before running the script, manually select objects with opacity masks.
  Use the free SelectMenu plugin by Rick Johnson to select masks https://rj-graffix.com/downloads/plugins/.
  Select > Object > Special Art Types > Opacity Masks

  *************************************************************************************************
  * WARNING: Don't put this script in the action slot for a quick run. It will freeze Illustrator *
  *************************************************************************************************

  Author: Sergey Osokin, email: hi@sergosokin.ru
  Check my other scripts: https://github.com/creold
  
  Donate (optional):
  If you find this script helpful, you can buy me a coffee
  - via Buymeacoffee: https://www.buymeacoffee.com/aiscripts
  - via Donatty https://donatty.com/sergosokin
  - via DonatePay https://new.donatepay.ru/en/@osokin
  - via YooMoney https://yoomoney.ru/to/410011149615582
*/

//@target illustrator
app.preferences.setBooleanPreference('ShowExternalJSXWarning', false); // Fix drag and drop a .jsx file

function main() {
  if (parseFloat(app.version) < 16) {
    alert('Wrong app version\nSorry, script only works in Illustrator CS6 and later', 'Script error');
    return false;
  }

  if (!app.documents.length || !app.selection.length) return;

  var isReady = confirm('This script requires you to select opacity masks only to correct sharp edges. Have you selected them only?');
  if (!isReady) return;

  var doc = app.activeDocument;
  var sel = get(doc.selection);
  doc.selection = null;

  var tmpLay = doc.layers.add();
  tmpLay.name = 'Remove This Layer';

  var action = {
    set: 'OpacityMaskFix',
    rlsName: 'Release_mask',
    mkName: 'Make_mask',
  }

  addOpacityAction(action);

  app.userInteractionLevel = UserInteractionLevel.DONTDISPLAYALERTS;
  try { 
    grayToBlackMask(sel, tmpLay, action);
  } catch (err) {} 

  app.userInteractionLevel = UserInteractionLevel.DISPLAYALERTS;
  doc.selection = null;
  tmpLay.remove();
  try { 
    app.unloadAction(action.set, '');
  } catch (err) {}
}

// Convert Grayscale mask to RGB via rebuild opacity mask
function grayToBlackMask(arr, lay, action) {
  var doc = app.activeDocument;
  var i = arr.length - 1;

  while (i > -1) {
    var item = arr[i];

    if (item.typename === 'GroupItem' && item.pageItems.length) {
      grayToBlackMask(item.pageItems, lay, action);
    } else {
      var tmpItem = item.layer.pathItems.add();
      tmpItem.name = 'Remove_this';
      tmpItem.move(item, ElementPlacement.PLACEBEFORE);
      doc.selection = null;

      // Edit opacity mask in a temporary layer to avoid errors on PC
      item.move(lay, ElementPlacement.PLACEATBEGINNING);
      item.translate(0, 0); // Fake move
      item.selected = true;

      try {
        // Release opacity mask
        app.doScript(action.rlsName, action.set);
        tmpItem.selected = false;

        if (doc.selection.length >= 2) {
          var mask = doc.selection[0];
          var art = doc.selection[1];
  
          doc.selection = null;
          mask.selected = true;
          // Run Edit > Edit Colors > Convert to RGB
          app.executeMenuCommand('Colors9');

          doc.selection = null;
          mask.selected = true;
          art.selected = true;
        }
  
        // Make opacity mask
        app.doScript(action.mkName, action.set);

        doc.selection = null;
        lay.hasSelectedArtwork = true;
      } catch (err) {}

      for (var j = doc.selection.length - 1; j >= 0; j--) {
        doc.selection[j].move(tmpItem, ElementPlacement.PLACEBEFORE);
      }

      tmpItem.remove();
    }

    i--;
  }
}

// Convert collection into standard Array
function get(coll) {
  var result = [];
  for (var i = 0, len = coll.length; i < len; i++) {
    result.push(coll[i]);
  }
  return result;
}

// Load set of actions in Illustrator to release and create opacity masks
function addOpacityAction(data) {
  var path = Folder.myDocuments + '/Adobe Scripts/';

  if (!Folder(path).exists) Folder(path).create();

  var actionCode = '''/version 3
  /name [ ''' + data.set.length + '''
    ''' + ascii2Hex(data.set) + '''
  ]
  /isOpen 1
  /actionCount 2
  /action-1 {
    /name [ ''' + data.mkName.length + '''
      ''' + ascii2Hex(data.mkName) + '''
    ]
    /keyIndex 0
    /colorIndex 0
    /isOpen 0
    /eventCount 1
    /event-1 {
      /useRulersIn1stQuadrant 0
      /internalName (ai_plugin_transparency)
      /localizedName [ 12
        5472616e73706172656e6379
      ]
      /isOpen 1
      /isOn 1
      /hasDialog 0
      /parameterCount 1
      /parameter-1 {
        /key 1835101029
        /showInPalette 4294967295
        /type (ustring)
        /value [ 0
  
        ]
      }
    }
  }
  /action-2 {
    /name [ ''' + data.rlsName.length + '''
      ''' + ascii2Hex(data.rlsName) + '''
    ]
    /keyIndex 0
    /colorIndex 0
    /isOpen 0
    /eventCount 1
    /event-1 {
      /useRulersIn1stQuadrant 0
      /internalName (ai_plugin_transparency)
      /localizedName [ 12
        5472616e73706172656e6379
      ]
      /isOpen 1
      /isOn 1
      /hasDialog 0
      /parameterCount 1
      /parameter-1 {
        /key 1919710053
        /showInPalette 4294967295
        /type (ustring)
        /value [ 0
  
        ]
      }
    }
  }''';

  try { 
    app.unloadAction(data.set, '');
  } catch (err) {}
  createAction(actionCode, data.set, path);
}

// Create an Adobe Illustrator action from the given action code
function createAction (str, set, path) {
  var f = new File('' + path + '/' + set + '.aia');
  f.open('w');
  f.write(str);
  f.close();
  app.loadAction(f);
  f.remove();
}

// Convert ASCII characters to their corresponding hexadecimal representation
function ascii2Hex(hex) {
  return hex.replace(/./g, function(a) {
    return a.charCodeAt(0).toString(16)
  });
}

// Run script
try {
  main();
} catch (err) {}

Important tips before using the script:
1️⃣ Select objects before running the script. For numerous masks, try the free SelectMenu plugin: Select → Object → Special Art Types → Opacity Masks.
2️⃣ Don't add the script to an action – Illustrator might freeze when triggered from an action.
3️⃣ Running the script via File menu results in a single action in the document history. Alternative methods capture processing steps for all objects.