Developer reply by squib
Rated 4 out of 5 stars
I can't put 5 stars today because your extension does not allow me to modify and save my set of columns in the thread pane. Every time I try to add some more columns, your extension turn the set of columns to its default.
Please, do anything not to interfere with the thread pane.
This add-on doesn't touch the thread pane at all, and I tried to add more columns myself and it works fine. Chances are you have something else disrupting the thread pane.
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