I've used Outlook 2013 to manage my gmail for a number of years. I recently received an email from google stating that versions of Outlook 2016 and earlier will no longer work for gmail after 5/30/22. According to them, only newer versions of Outlook will offer the required "sign-in with Google" option. If this is correct, I'd like to move away from Outlook because the newer versions of Outlook may not work with my Windows 8.1 OS. To avoid the expense and possibility that a new version of Outlook may not work on my PC, I'm exploring Thunderbird. I'm very concerned about losing emails both in my inbox and the sub-folders I've created within my inbox. Am I correct in assuming that since I'm on an IMAP protocol with google that I'd be able to pull all of that same email from my inbox, and sub-folders within my inbox directly into Thunderbird? If my assumption is correct, will Thunderbird upon import automatically set up the same sub-folders with contents under my new inbox? I know that I have some cleaning up to do, is there a size limitation on how much Thunderbird can handle? Thank you!