I use Thunderbird calendar for all my events and without it I am lost. Yesterday, I wanted to export my calendar to be imported later by an online platform. I used the export function. I noticed however, that under the name of my calendar on the left pane this has appeared ( . export). I thought the ics file is already created, so I went ahead and deleted the strange ". export" item that appeared under my calendar name in the left pane. What happened next was that all my events disappeared from my normal calendar window. My question is how I can get back all my events? Or how I can restore the ". export" so my events come back.

Additional information: I did not have backup for my calendar. I cannot locate anywhere the ics file I thought it is "exported" I am using the latest version of Thunderbird as of March 2024.