page.objs.get Pauses When Processing Multiple Images

[fallingleaflun]

I tried snippet from #14542, and it looks like this:

for (const i of rawImgOperators) {
    const imgIndex = operatorList.argsArray[i][0];
    await new Promise<void>((resolve) => {
        page.objs.get(imgIndex, async (imageRef: any) => {
            const canvas = document.createElement('canvas');
            canvas.width = imageRef.width;
            canvas.height = imageRef.height;
            const context = canvas.getContext('2d');
            if (!context) {
                resolve();
                return;
            }

            const data = new Uint8ClampedArray(imageRef.width * imageRef.height * 4);
            if (imageRef.data.length === imageRef.width * imageRef.height * 3) {
                let k = 0;
                let i = 0;
                while (i < imageRef.data.length) {
                    data[k] = imageRef.data[i]; // r
                    data[k + 1] = imageRef.data[i + 1]; // g
                    data[k + 2] = imageRef.data[i + 2]; // b
                    data[k + 3] = 255; // a
                    i += 3;
                    k += 4;
                }
            } else if (imageRef.data.length === imageRef.width * imageRef.height * 4) {
                data.set(imageRef.data);
            } else {
                console.error('Unsupported image format');
                resolve();
                return;
            }

            const imgData = context.createImageData(imageRef.width, imageRef.height);
            imgData.data.set(data);
            context.putImageData(imgData, 0, 0);

            const imgBlob = await new Promise<Blob | null>((resolveBlob) => canvas.toBlob(resolveBlob));
            if (imgBlob) {
                images.push(imgBlob);
            }
            resolve();
        });
    });
}

It works fine when there are only a few images. However, when I repeat the same page and get a PDF that contains many images, I find that after several loops, the breakpoint stops at await new Promise<void>((resolve) => {, and then the program pauses. The line const canvas = document.createElement('canvas'); is never reached.

Could anyone help me understand why this is happening and how to fix it?

[fallingleaflun]

I find that if an image is repeated, then page.objs.get will definitely pause. For example:

const imgIndex = operatorList.argsArray[i][0];

The first time imgIndex is "img_p1_1", the callback succeeds. The second time, for the repeated image, imgIndex is "g_d0_img_p2_1", and the callback does not execute.

[fallingleaflun]

imgIndex starts with "g_" should be obtained with page.commonObjs.get(
#13742 (comment)