The only major shortcoming of Thunderbird and PostBox is the inability to easily organize and manage a large collection of folders. That's where QuickFolders comes into play.
QuickFolders offers a easy, quick, and sensible way to organize and manage folders. It is a lightweight, unobtrusive, and stable extension. Also, it comes with other several useful features. Additionally, the Developer quickly answers all support requests and goes the extra distance to deliver great customer service.
The FREE version is adequate. But the extra features in the Pro version are well worth the small cost of $15. Plus, that $15 helps to keep the developer in business and updating QuickFolders. I urge all to buy the Pro version.
THERE IS ONE SMALL CATCH WITH THE PRO VERSION'S LICENSE for those who use multiple email clients on the same PC...but there is an easy fix. I will explain.
The Pro license is 'assigned' to one specific email address...which is the email used when purchasing the license. That licensing method can cause an issue when using multiple email clients. Here's how.
The QuickFolders extension works in both Thunderbird and PostBox. (Postbox is Thunderbird optimized for Gmail.) BUT the Pro License will register to only one of the two email clients. Thus, a second Pro license is required to get Pro to work in both email clients.
(I use Thunderbird strictly for my Microsoft email accounts. Then I use PostBox for my gmail accounts.)
I BOUGHT THE PRO LICENSE UNDER MY GMAIL ADDRESS. Therefore, I can only use the Pro License in an email client 'hosting' that gmail address, which is PostBox. CONSEQUENTLY, I can NOT use the Pro License in Thunderbird (because I don't do gmail in Thunderbird).
The Pro Licensing System requires buying multiple Pro licenses when using different email clients installed on the SAME PC. But there is an easy fix.
If you find yourself in the predicament described above, email the developer Axel Grude and tell him. Then the Developer will fix things so that the purchase of one Pro license will register QuickFolders Pro in all email clients on the same PC.
This review is for a previous version of the add-on (4.5).
"BUT the Pro License will register to only one of the two email clients"
you're misinformed. The pro license is registered to one specific email address, but this can absolutely be used on multiple / different Thunderbird / Postbox / SeaMonkey installations, both on the same and separate machines. The email address is the key, not the number of installations. If you think you experience something else, I will need to debug the problem because as I describe is the way I have designed it. I will not rule out that you may have found a bug although I doubt it at this stage.
you can used it on many installations, you just need one common email address to verify your license, but you can have 10 or more additional email addresses.
If you want to use 2 different mail addresses on 2 separate accounts (and not share the same key), then please get in touch and I can give you a free license for your second use. I just need to know the second address.
It is just technically very difficult to "spy" different installations on the same system (on 3 different operating systems, Windows/Linux/Apple this would be several weeks of work and may prove unreliable) and email addresses are much easier to verify as unique. I have no problem in providing a second free license, just get in touch instead of doing a review because I cannot help you that way. There is a link on the options dialog to get in touch.
I am still working with the customer to resolve this situation - I believe there is a mismatch between email addresses. E.g. old gmail.com addresses used to end with googlemail.com which may be one possible explanation for the problem.