This article applies to Suitcase Fusion for Mac versions 21 and later, all versions of Connect Fonts for Mac, and Macs on macOS High Sierra (10.13) and later.
Some fonts do not display an actual preview, showing a greyed-out generic preview instead. In Activity Monitor, the FMRenderer process may take up a large percentage of CPU and memory usage. Restarting the Mac helps for a short period of time, but the problem can return due to problematic fonts being stored in the font library.
The FMRenderer process is used by Connect Fonts or 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 Connect Fonts or 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 affected fonts missing previews from Suitcase Fusion and restart the type core. You can identify potential problem fonts in your font collection by looking for fonts with generic font previews.
You should collect the problem fonts from the Connect Fonts or Suitcase Fusion font vault before removing them completely. For more information, go to Collecting fonts from the Connect Fonts font vault.
Select the problem fonts and choose Edit > Delete. Connect Fonts or Suitcase Fusion will display a dialog asking you if you want to remove the fonts from the current library or remove them from the application entirely. Click Remove from Connect (or Remove from Suitcase).
Once the fonts have been removed, choose the Preferences option in the menu bar. Click “Stop Type Core”; the app will then close and the FMRenderer process will quit.