Replace jasperreports-fonts.jar with a patched version from 6.6.1.

For more information on Jaspersoft Studio 6.6.0 and related topics, check out the following resources:

If you cannot find the 6.6.0 installer, you can download a newer version (like 6.20+) and use Compatibility Mode . Go to Properties > Jaspersoft Studio > Compatibility to set the compiler to target version 6.6.0 specifically. Common 6.6.0 Fixes & Optimizations

Jaspersoft Studio 6.6.0 Very Slow Poor Performance - Products

Are you experiencing a or performance issue that requires a fix for this version?