Remove Duplicate Messages

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wót Robbie Wilkes dnja Jan. 26, 2016 · trajny wótkaz

Decided to give Thunderbird a try because I found out about this add-on which would, hopefully, allow me to clean up my inbox. However, in looking at the configuration, one of the simplest and most common sense options would be to delete OLDEST duplicates... but, instead, it only allows for "first found". Am I missing something in the way this is worded? Please help... I would LOVE to be able to utilize this extension.