I've been using Thunderbird and its Calendar for MANY years very happily :-) My old main computer is a w7 Lap and the Thunderbird Calendar in that version has the option to set up a Reminder Notification via Email. And it still works with no problem! I just was given a used Laptop computer that I did a clean install of w11 on, and installed Thunderbird and setup the Thunderbird Calendar to my Google Calendar with NO problems! EXCEPT: I just created a New Event and a Reminder for it, and to my chagrin, there is NO option to be notified by Email anymore !!! grrrrrr  :-( Please, I beg the developers to reinstate that option ! I use that for every event that I create! eg I take MEDS and when I get the email reminder, I can delete the Email reminder to show myself that I've taken that med at that time !!!! Please advise ! THANK YOU