Howdy, folks. I wanted to report a very minor bug, but I believe a bug nonetheless. I am unsure what part of the program is responsible for this error. I recently downloaded a copy of Neptune 6.5 and installed it, which went quite well. Neptune is a great distro, btw. However, when I went to test the printer that installed out-of-the-box by attempting to print a test page, it failed to print, indicating an error of "filter failed." Thinking that meant that the printer wouldn't work for anything else (a false assumption on my part), I began a long 2-day process of trying to figure out what was wrong. Then I finally found out where the error log was at, checked it, and it said something along the lines of not being able to locate the "default-testpage.pdf" file in the "/usr/share/cups/data" directory. So I checked that directory to discover a file named "default-testpage.pdf.distrib".
To make a longer story shorter, I figured out (after two reinstalls of the system) that if I printed anything else, like a test I did from Kwrite, it would print that. It was only that one test page that failed to print. All I did to "fix" it was to remove the ".distrib" from the end of the file, which enabled CUPS to find the file and print it.
I am a "small time" YouTube creator (currently at 23 subscriptions) and I focus on Linux. I plan on featuring the Neptune OS in a future review, in my "New User Linux Review" series. Having figured out that it will print out-of-the-box, means I'll be able to give it a higher score than I originally did. Thank you and I hope you find this helpful. Let me know if you need to know anything else.