Here is a brief, accurate response you can use for the Thunderbird forum: ​By default, Thunderbird sorts folders in a specific hierarchy (like Inbox, Drafts, Sent, Trash first) and then alphabetically for custom folders. It does not automatically sort them by the "creation date." ​If your custom folders are not sorting alphabetically, or if you want to order them exactly how you like, here are the solutions: ​1. Manual Sorting (Thunderbird 102 and newer) ​You can easily drag and drop folders into any order you prefer: ​Click and hold the folder you want to move. ​Drag it up or down to your preferred position and release. ​2. Force Alphabetical Sorting ​If your custom folders are out of order and you want to force them back into alphabetical order: ​Right-click on your account name (the main email folder at the top of the list). ​Select Settings. ​(Optional) For advanced control over folder behavior, you can look into the Advanced Preferences (about:config) and search for mail.account.accountX.folder_order, but dragging and dropping is the recommended way in modern versions. ​3. Use an Add-on for Advanced Sorting ​If you have a very large number of folders and want automated, strict sorting rules, you can install a community extension: ​Go to Settings > Extensions & Themes. ​Search for and install Manually Sort Folders. This add-on gives you full control over account and folder ordering if the built-in drag-and-drop isn't enough.