If you're using languages such as Japanese, Korean, Arabic, etc in your looks and dashboards, chances are the looks and dashboards look fine in your browser. This is because most PC's and Macs (and even desktop Linux installations) include all the fonts required to render those character sets by default.
However, if you scheduled a visualization of a look, or download a dashboard PDF you may note empty space or those dreaded little rectangles where your characters were meant to be. This is because the "browser" in this case is actually running on the machine hosting your Looker.
This can be solved by having your administrator install the correct fonts for your platform on the instance that runs Looker. (Note that if you run Looker in a cluster, you should install these on every node of the cluster.)
Unfortunately there is no single set of instructions that I can quote here. Each Linux distribution has its own packaging system and some even have access to different font sets. Google can be your friend here
As an example, installing support for Japanese character sets on a Ubuntu box requires an admin with root access to the Looker instance to run the following command:
apt-get install fonts-takao
If you host your own Looker instance and are struggling with finding the right fonts package, ping us and we'll try and help.
And if your Looker instance is hosted by Looker, please contact support to have our operations team install the proper font packages on your behalf.