Slow Performance in Illustrator cc 2020 24.3 Mac Catalina

Hi Gareth,

Sorry to hear about your experience. You may try following the steps below and share your observations:

1. Reset Preferences: - 

• Close all Adobe applications. 
• Go to locations 
• ~/Library/Caches 
• ~/Library/Application Support/Adobe 
• ~/Library/Preferences 
• Rename  Adobe Illustrator, com.adobe.illustrator and Adobe Illustrator 24 Settings folders to Adobe Illustrator.old, com.adobe.illustrator.old and Adobe Illustrator 24 Settings.old 
• Launch Illustrator from the Creative Cloud. 

**Please note that resetting preferences will remove all the custom settings and Illustrator will launch with default settings. This way all your old settings will be saved in .old folders and Illustrator will recreate new folders with default settings.  

2. If that doesn't help, try booting the system into Safe Mode (https://helpx.adobe.com/in/x-productkb/global/start-safe-boot-mode-mac.html) and check how it works there. It starts your system so that it performs certain checks and prevents third party software/ services from automatically loading or opening. If it works fine in Safe mode, then there is some third party service or application like antivirus, plugins or web extensions which are conflicting with the Illustrator. 

3. If that doesn't help either, login to root account (https://support.apple.com/en-in/HT204012). Check how application works there. If it works fine there, then it could be related to permission errors. Follow these steps to repair permission errors: https://helpx.adobe.com/in/illustrator/kb/preferences-folder-read-only-error.html  

Hope it helps.

Regards,

Ashutosh