translates to english as "doc file can't be found at location /usr/share/doc/kicad/help/../footprints_doc/footprints.pdf" also as you can see in the console the file is present at location /usr/share/doc/kicad/help/footprints_doc/footprints.pdf
translates to english as "doc file can't be found at location /usr/share/ doc/kicad/ help/.. /footprints_ doc/footprints. pdf" doc/kicad/ help/footprints _doc/footprints .pdf
also as you can see in the console the file is present at location /usr/share/