This article applies to Suitcase Fusion for Mac versions 21 on macOS High Sierra (10.13) through macOS Catalina (10.15).
Some fonts do not display an actual preview, showing a greyed-out generic preview instead. In Activity Monitor, the FMRenderer process takes up a large percentage of CPU and memory usage. Restarting the Mac helps for a short period of time.
The FMRenderer process is used by Suitcase Fusion to generate preview samples of fonts. Fonts with highly-complex outlines for its character glyphs, such as “clip art” fonts, can drive up CPU and FMRenderer usage until the font has been processed. If Suitcase Fusion is allowed to finish generating the previews,the FMRenderer process will return to normal.
In some cases, the fonts never complete processing, and the high CPU and memory will persist. If this happens, you should remove the fonts from Suitcase Fusion and restart the type core. You can identify potential problem fonts in your Suitcase Fusion library by looking for fonts with generic font previews.
You should collect the problem fonts from the Suitcase Fusion font vault before removing them completely. For more information, go to Collecting fonts from the Suitcase Fusion font vault.
Select the problem fonts and choose Edit > Delete. Suitcase will display a dialog asking you if you want to remove the fonts from the current library or remove them from Suitcase entirely. Click Remove from Suitcase.
Once the fonts have been removed, choose Suitcase Fusion > Preferences. Click “Stop Suitcase Fusion Type Core”; Suitcase Fusion v21 will close and the FMRenderer process will quit.