It seems that mantis can never remember my password, so I’m noting this here…
Updater fails with this error
Starting integrity check
The following files are not expected or are required:
.well-known
mo
robots.txt
Shouldn’t it just ignore my private folders (e.g. mo)??
And .well-known is required for our SSL certificate…
@mikerotec You might want to try a plugin that I have developed to upgrade phplist. It does not have the restrictions of the core phplist updater regarding unexpected files and additional plugins.
@mikerotec For now it’s best if you move those files out and then move them back after the update completes. Some of these files should be handled automatically in future. If you want to help with that then the source code is awaiting your pull request 
: https://github.com/phpList/Updater