Leftovers in AppData

v60.8: In AppData, I get the folders Local\Thunderbird\updates and Roaming\Thunderbird\Pending Pings. Both empty. I have diabled updates in Thunderbird. No idea what the second one is exacly there for.
I use the following add-ons: Lightning, Manually Sort Folders, ImportExportTools.
Thunderbird Portable is located on a different partition than the system (and AppData). I never had an installed version of Thunderbird on this machine.
Shouldn't the launcher take care of these folders?
Am I doing anything wrong or is that known?