What format of pictures do you want to add? Is it big? I tried it carefully just now, and found that if it is a screenshot or a picture in normal size jpg and bmp format, it can be copied and pasted directly into the signature file. You can try. If the picture itself is relatively large, I suggest you make it smaller by taking screenshots, or if you don't bother, you can use some tools to convert the picture format smaller, and so on.