Thanks for your feedback.

Cause:

The latest versions of Safari use a plug-in manager for enabling and disabling plug-ins on a global or per site basis.

Solution:

To resolve this issue trust the Webex64 General Plug-in Container.

To trust the Webex Plug-in for Safari:

1. Choose Safari > Preferences > Websites.
2. From the left panel, under Plug-ins, choose 'Webex64 General Plug-in Container'.
3. For all sites listed on the right, select On.
4. Next to the option for 'When visiting other websites', select On:
   
5. Quit and restart Safari.
6. Try to join or start your meeting again.

• Verify the Webex site you are joining on supports the Mac OS version you are using.
  • Webex Meetings Suite System Requirements

• Exit any open web browsers and uninstall the Webex meeting software from your Mac, then try to start or join a meeting again.
• If you are still unable to join a meeting, create a new user profile on your Mac, then try to start or join a meeting with the new user profile.
  • See: WBX55020 - How Do I Create a New User Profile on a Mac?

Firefox and Chrome users, please refer to:

• WBX77970 - How Do I Enable the Webex Plug-in to Join a Meeting Using Chrome or Firefox?