The default startup folder can be set with Manually Sort Folders (see picture). There is a beta version that works in TB 60:

http://forums.mozillazine.org/viewtopic.php?p=14811751#p14811751

https://support.mozilla.org/en-US/kb/installing-addon-thunderbird

Yes, this worked. Thank you for the tip.

I saw this when I was looking to upgrade to Manually 1.1.1, but I could not download it. It tried to install it to my Waterfox browser when I clicked on it. I was being thick then. This time I realised I could obtain it by saving link as to my downloads folder and install it to addons using the Install from a file option.

Thank you!!!! It is clearer to me that there exists some problem, I did not follow precisely what, that prevents this from working in Thunderbird in the 60 range. When I installed the Manually version good up to 63, I thought I had a better version than github's patch.

I am grateful for your assistance!!!

I wish Thunderbird would incorporate this function. It makes Thunderbird so much nicer to customize!!

Being able to choose more aesthetic rounded tabs would be nice to. If I wanted Chrome features, I would use Chrome. I like Mozilla!!!!!

Thank you all you great people for these amazing products. I am an obsolete apps programmer (prior to event driven and object oriented), or I would offer to help.

All the best Happy Holidays to you all!

looking for a version of Manually Sort Folders that is compatible with Thunderbird Version 66