I have been using a couple of old Thunderbird add-ons, that aren't listed on the Epyrus add-ons site, that seem to work well and are quite useful, so I thought I'd mention them in case they are useful for others. I'm pretty sure that these work on the default gtk-3 version as well as my gtk-2 version.
CompactHeader 2.1.3 allows the display of more compact headers on emails
https://addons.thunderbird.net/en-us/th ... sion-2.1.3
Import Export tools 3.3.2 allows me to back up and restore my email profile and I have also used it to transfer profiles from Interlink to Epyrus.
https://addons.thunderbird.net/en-us/th ... sion-3.3.2
https://freeshell.de/~kaosmos/mboximport-en.html
People may have found other useful add-ons that work with Epyrus?
CompactHeader 2.1.3 allows the display of more compact headers on emails
https://addons.thunderbird.net/en-us/th ... sion-2.1.3
Import Export tools 3.3.2 allows me to back up and restore my email profile and I have also used it to transfer profiles from Interlink to Epyrus.
https://addons.thunderbird.net/en-us/th ... sion-3.3.2
https://freeshell.de/~kaosmos/mboximport-en.html
People may have found other useful add-ons that work with Epyrus?