Need help from the forumers here.

I have an old photo (more than 30 years old) that is partly stuck to the glass in the photo frame.

I have googled this problem and it seems that many have recommended soaking the photo and glass in water (some say icy, some say room temperature) and allow the photo to detach from the glass.

Anyone here has done this before? Or had faced the same problem? How did you fix this problem?

Many thanks in advance.