Rated 5 out of 5 stars

Thanks Philippe for your help - problem solved.

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For anyone´s reference:

Scrolling in E-mail-list is extremely laggy.
Could trace this problem back to this Add-in because after disabling this add-on everything smooth.

Gone back to v 21.3 - everything smooth again.
Windows 10, Thunderbird 52.2.1

Love this add-on - please make it useable again. Thank you!

This review is for a previous version of the add-on (21.5). 

in Thunderbird preferences, Display tab, uncheck the last option : "Show only display name for people in my address book" ;O)