I’ve opened a password protected file and when I save a new copy, the password is still included. This is a feature in Preview, and Acrobat has a feature that allows removing the encryption. How do I do this with Sumatra?
Sumatra doesn’t have such functionality.
Many viewers such as Edge allow you to open a file with a password and may then allow you to print or save as PDF.
However using “save as” in SumatraPDF will usually retain the need for the same password and will often require the same one of two passwords to save changes such as if you added comments.