slides_fonts_finder.gs

const desiredFonts = ["Quattrocento Sans","Proxima Nova"];
  
function checkFontUsage() {
  // Access the active presentation
  var presentation = SlidesApp.getActivePresentation();
  var slides = presentation.getSlides();
  
  // Define the desired font
  
  // Iterate through all slides
  for (var i = 0; i < slides.length; i++) {
    var shapes = slides[i].getShapes();
    
    // Iterate through all shapes on the slide
    for (var j = 0; j < shapes.length; j++) {
      try {
        // Check if the shape contains text
        let shape = shapes[j];
        let shapeText = shape.toString();
        let slide = (i + 1);
        let type = shape.getPageElementType().toString();
        let textRange = shape.getText();
        let text = textRange.asString();
        let hasNoText = /^\s+$/.test(text);
        if (textRange && !hasNoText) {
          var textStyle = textRange.getTextStyle();
          var actualFont = textStyle.getFontFamily();
          // Check the font of the text
          if (actualFont && !(desiredFonts.includes(actualFont))) {
            Logger.log('Slide ' + (i + 1) + ': uses :' + actualFont + ' for text "' + textRange.asString() + + '",' + type);
          }
        }
      } catch (ex) {
        
      }
    }
   
  }
}