Email, Messaging, & Video Calls Email How to Group Messages in Mozilla Thunderbird Group by sort order to focus on the most important emails by Heinz Tschabitscher Writer A former freelance contributor who has reviewed hundreds of email programs and services since 1997. our editorial process Heinz Tschabitscher Updated on October 03, 2018 Alex_Doubovitsky / Getty Images Email Yahoo! Mail Gmail Tweet Share Email Organize your emails more efficiently by having Mozilla Thunderbird group them. To Hide and Not Seek Having your Inbox or your archived mail sorted by date is useful in Mozilla Thunderbird, but it can make your mailbox look overwhelming, so concentrating on the most recent messages becomes a daunting task. Is there not a way to hide the old messages temporarily? There is. Mozilla Thunderbird can group and collapse messages according to your chosen sort order. If you are sorting by date, you have a group of emails received today, a group for mail received yesterday, a group for last week's messages, and so on. It's easy to minimize the impact of all old mail in this way. Group Messages in Mozilla Thunderbird To group messages in Mozilla Thunderbird: Open the folder that contains the messages you want to group by sort order. Select View > Sort by > Grouped By Sort from the main Mozilla Thunderbird menu or the Thunderbird menu you reach by clicking the menu button formed by three horizontal lines that is located in the upper right corner of the mail screen. Unfortunately, not all the options by which you can sort a Thunderbird folder support grouping. For example, sort orders that do not allow grouping include Size and Junk Status. If you cannot group your messages according to the current sort order, the Grouped By Sort menu item is grayed out. To return your folder to an ungrouped state, select View > Sort by > Unthreaded or View > Sort by > Threaded from the menu.