Hi Ronin, do you have a different online service where you store your appointments, or did you want to store appointments only on your computer, or do you want to display a calendar for general reference and not use it for saving appointments?

Firefox add-ons can lose data if they are ever uninstalled or if their database becomes corrupted. It would be safer to save appointments in the cloud (even if not using a Google service) or in a dedicated calendar program with more robust data storage.

Ok you provided a "generalized" response.. thanks for the effort, but I was looking for a direction to an extension that works. I went for one on Firefox. I'll keep looking... maybe there is one that suits my need.

Hmm, if you want more help with your extension search, please provide more information on what you want the extension to do. So far, the only thing we know is that it should not use Google Calendar.

Is it okay if it uses Outlook? https://outlook.live.com/owa/

Do you want it to load a cloud calendar in a new tab? New pop-up window? Sidebar? Etc.