Hello,
I have experience in developing extensions for Thunderbird with using both old and new API.
Shortcuts can be added with using commands API [1] or directly by listening KeyboardEvent event [2]. But I myself have never used keyconfig [3], so I need to look at it.
However, I must note that I can only start work at the end of the week and finish on the next week.
I will be happy to discuss the project and answer your questions. We can also discuss the price and terms.
Thank you for attention!
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