Broke site on first use, uninstalled

I don’t understand what it did, but thank goodness I first backed up the site and database. After letting SG Optimizer clean the DB and then other recommended tasks, my posts no longer loaded but instead gave a page not found error. Restoring from backup fixed it back.

I’m a long time Siteground customer and they are the best hosting company one could want. But, this plugin — I wonder if they even know that it can break a simple vanilla site with lots of posts?

Oh well.