Review for CategoryManager by WolfgangKlein
Rated 5 out of 5 stars
To every one who experienced an empty category list after updating to the latest version: this little bug can be killed by installing the addons cat.man and sogo in the right order: uninstall cat.man completely, update to the latest sogo, and reinstall cat.man.
John told me so, and he is already working on a better fix for this.
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