Oh I see. That's quite an old version of unpaper. The current version is 6.2. Does pdfsandwich crash at this point, or does it proceed despite the error message?
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Oh I see. That's quite an old version of unpaper. The current version is 6.2. Does pdfsandwich crash at this point, or does it proceed despite the error message?
As this happens only for very old versions of unpaper, this shouldn't be a problem anymore. I'll close this bug.
Unpaper version is now (pdfsandwich 0.1.5) checked with -V, which should work with any version of unpaper.