Motion Firefox - All-in-one time management tool in Firefox
Cal.et - Add to Calendar Link Generator
FocusList - Daily planner & focus timer based on timeboxing and pomodoro
AddEvent - AddEvent is an Add to Calendar button for one-time and multiple events.
Teeny Breaks - Mindfulness tips to make the most of your breaks 🧠💖
Microsoft Outlook Calendar - Calendar is a time-management web application by Microsoft.