Viewer:  https://mozilla.github.io/pdf.js/web/viewer.html
Chrome on Windows 10
When the attached PDF file is viewed, some of the fonts display as garbled text. 
[Arial, Courier, Times New Roman]
The file views correctly in Adobe Reader.
[fff.pdf](https://github.com/mozilla/pdf.js/files/4652174/fff.pdf)

if (nameEntry === part) {
                fallbackData = {
                  name: part,
                  header: potentialHeader,
                  tables: potentialTables,
                };
              }
            }
          }
        }
      }
      if (fallbackData) {
        warn(
          `TrueType Collection does not contain "${fontName}" font, ` +
            `falling back to "${fallbackData.name}" font instead.`
        );
        return {
          header: fallbackData.header,
          tables: fallbackData.tables,
        };
      }
      throw new FormatError(
        `TrueType Collection does not contain "${fontName}" font.`
      );
    }
    /**
     * Read the appropriate subtable from the cmap according to 9.6.6.4 from
     * PDF spec
     */
    function readCmapTable(cmap, file, isSymbolicFont, hasEncoding) {