My past and current projects
If you exported your email using Google Takeout or other services, you might have ended up with an MBOX file. To have access to those emails, you can import that file into Thunderbird, here’s how:
First you need to rename the file to something that Thunderbird will understand. Usually the file will have a long name and an mbox extension, for example: “ All mail Including Spam and Trash.mbox “. Rename the file to a single word without any extension, like MyMail for example. This name will be the folder name in your email, so pick whatever you want to see there.