I see there is a command to "rename file from parent metadata" but is there any way to do this automatically, so that newly downloaded PDF attachments use the parent metadata for naming in the first place?
Yes, this already happens automatically when you save from the web and can't be turned off (since those files often don't have actual filenames).
If "Automatically rename attachment files using parent metadata" is enabled in the General pane of the preferences (which it is by default), it will also happen for files you add from your computer (and, optionally, for files you link, though that's not enabled by default).
Note that the attachment title isn't always the same as the filename (e.g., when a translator can use a more descriptive name for the attachment).
It did not happen with files added from an RSS feed.Instead it named the file "full text." The option in the general preference pane is (and was) turned on.
I will keep an eye out to see if it ever happens with items added from the web using the Chrome extension.I think it might have, but this would be unexpected so perhaps I am wrong.If it happens again I will try to keep notes and report it.
Note that the attachment title isn't always the same as the filename (e.g., when a translator can use a more descriptive name for the attachment).
You can see the filename by looking at the Filename field in the right-hand pane after clicking on the attachment or by using right-click → Show File."Full Text PDF" or similar would be the attachment title, not the filename.
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If "Automatically rename attachment files using parent metadata" is enabled in the General pane of the preferences (which it is by default), it will also happen for files you add from your computer (and, optionally, for files you link, though that's not enabled by default).
Note that the attachment title isn't always the same as the filename (e.g., when a translator can use a more descriptive name for the attachment).
I will keep an eye out to see if it ever happens with items added from the web using the Chrome extension.I think it might have, but this would be unexpected so perhaps I am wrong.If it happens again I will try to keep notes and report it.