BirdieSync

I have BirdieSync 3.2.5.1
Thunderbird 78.14.0

When I install BirdieSync it recognizes that I am running Thunderbird and asks me to shut it down.
However, when I restart Thunderbird there is no BirdieSync Add-on in Thunderbird.

I have tried clearing Thunderbird cache. Removing BirdieSync, re-adding it.
I have tried deleting extentions.sqlite in C:\Users\<user>\AppData\Roaming\Thunderbird\Profiles as suggested in an older forum post.

Nothing that I have done is adding BirdieSync to Thunderbird.

Hope you can help.

Thank you.

Just noting that Thunderbird 78.14.0 (64-bit) is the latest channel release dated Sept 7, 2021
Still looking for a reply.
Thank you.

I'm using Thunderbird 78.14.0 with BirdieSync V.3.2.4.3 and it's working fine.

BirdieSync V.3.2.5.1 has the support for Thunderbird 91, which is on beta. Are you sure this release is supposed to work with Thunderbird 78? I haven't read anything to the contrary in the forum, but in the past BirdieSync releases that supported new versions of Thunderbird were mostly incompatible with the old version of Thunderbird.

Well, I tried to get this working about 6 months ago and could not.
I recently tried again and I just downloaded the latest BirdieSync installer without noticing the drop down to select the version of ThunderBird.

Thank you that was all very helpful.
So the latest 3.2.5.1 BirdieSync install is Not compatible with ThunderBird 78.
I might suggest an installer that validates the matching the prescribed version of Thunderbird.
Another area that proved confusing to me were the outdated BirdieSync install instructions on Thunderbird.
There is no Thunderbird Tools->BirdieSync menu item.
The setup image provided for Thunderbird shows an a cog icon for getting into Thunderbird BirdieSync setup, this does not exist for BirdieSync 3.2.4.3 and Thunderbird 78.
The key for me was finally seeing the small BirdieSync icon on the right most Thunderbird toolbar.
Appreciate your help.