Magento 2.3.3 problem: Error when uploading images on product page

I want to add a new product in my new Magento 2.3.3 webshop. When I upload a product image on this page, I see this:

https://i.stack.imgur.com/RUoPM.png

I looks like it would upload an other image, but I selected just 1.

Next, I will save the product but it isn’t possible (I press the button, but nothing happens)

When I look in my console from my browser I get the following error:

product-gallery.js:138 Uncaught TypeError: Cannot read property 'value' of undefined
at product-gallery.js:138
at Function.grep (jquery.js:471)
at $.<computed>.<computed>.setBase (product-gallery.js:133)
at $.<computed>.<computed>.setBase (jquery-ui-1.9.2.js:432)
at $.<computed>.<computed>._addItem (product-gallery.js:217)
at $.<computed>.<computed>._addItem (jquery-ui-1.9.2.js:432)
at HTMLDivElement.handlerProxy (jquery-ui-1.9.2.js:739)
at HTMLDivElement.dispatch (jquery.js:5232)
at HTMLDivElement.elemData.handle (jquery.js:4884)
at Object.trigger (jquery.js:5136)

This is line 138 in product-gallery.js

setBase: function (imageData) {
        var baseImage = this.options.types.image,
            sameImages = $.grep(
                $.map(this.options.types, function (el) {
                    return el;
                }),
                function (el) {
                    return el.value === baseImage.value; #LINE 138
                }
            ),
            isImageOpened = this.findElement(imageData).hasClass('active');

        $.each(sameImages, $.proxy(function (index, image) {
            this.element.trigger('setImageType', {
                type: image.code,
                imageData: imageData
            });

            if (isImageOpened) {
                this.element.find('.item').addClass('selected');
                this.element.find('[data-role=type-selector]').prop({
                    'checked': true
                });
            }
        }, this));
    },