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identitychooser-mx
A thunderbird mailextension for explicitely choosing the correct sender identity before opening an email editor.
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SurveyJS
Open-Source JSON Form Builder to Create Dynamic Forms Right in Your App. With SurveyJS form UI libraries, you can build and style forms in a fully-integrated drag & drop form builder, render them in your JS app, and store form submission data in any backend, inc. PHP, ASP.NET Core, and Node.js.
at first I thought about Identity Chooser [I use that], but being on mobile it was hard to check my Thunderbird & see if it is capable of what you need. now, as I am at desktop and was notified about your comment - I double checked and.. nope, Identity Chooser isn't what you're looking for BUT after some google-fu I've found this: Folder Account - it may be worth to check it out as it sounds promising as your problem's solution :)