fonts - Text has turned to boxes in Ubuntu 16.04

without cause can tell, text has turned boxes /rectangles everywhere in ubuntu 16.04.

i able press ctrl-alt-f1 , go shell, have run :

apt-get update

and

apt-get upgrade

but has not changed anything.

any suggestions?

this can result of invalid permissions settings on font files. need set correct permissions fonts.

to fix permissions of fonts ending .ttf or .otf extension use these 2 commands.

find /usr/share/fonts -iname '*.ttf' -type f -exec sudo chmod -v 644 {} \; find /usr/share/fonts -iname '*.otf' -type f -exec sudo chmod -v 644 {} \;

then use command re-build font cache

sudo fc-cache -r -v

this should fix problem.

Primitatvve