As reported by sites Betanews and Bleeping Computer, Microsoft Edge version 38.14393.1066.0 running the Microsoft EdgeHTML engine 14.14393, as well as Microsoft Edge 40.15063 running EdgeHTML 15.15063 produces some potentially alarming results.
In simple terms, if you view a PDF within Edge, and then print to PDF - it won't necessarily be the same as what went in. The example reported on the Microsoft Developer forum is that Edge prints "114447" instead of "123456".
I looked myself and found that using a sample file "original_file.pdf" provided at the Microsoft site, I was able to verify this issue. Note, my issues, were not the same as those originally reported by Matthias I., however, they were differences between the documents nonetheless.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.