Rated 3 out of 5 stars

This is a good add-on. However, I am having a problem.
I have it set to back up on exit, but since about April, I have been getting "_MSG_dialog.title" and when I press OK, the backup is not created.

Deleting the add-on and re-inserting it again does not improve the situation. Please let me know how to improve this issue.

This review is for a previous version of the add-on (14.0.2). 

Thanks for the review, sorry for the issue.
This is something already being patched. It should only be necessary to do the following :
On the backup options tab make sure the Use modal window is set. The non-modal option is no longer compatible.
This has solved the issue for other users. If it does not, please post to the github issue :
https://github.com/thunderbird/import-export-tools-ng/issues/559

Christopher