This is not something weird pgadmin does, but rather it is something weird Windows itself does when needing to represent such file names in a DOS-like setting. Like when the name is more than 8 chars, or extension more than 3.
In my hands the weird presentation is only there in the logs and status messages. If I use the GUI file chooser, the file names look normal, and replay successfully.
If you really want to know what Windows is doing, I think that is a better question for superuser with a Windows tag. I don’t know why you can’t restore these files. Are you using the pgAdmin GUI file chooser or trying to type the names in directly to something?
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