Xenforo was rated 5/5 stars, great, but it says Xenforo doesn't have the following:
Topic Tags: Available as an addon called Tinhte Xentag
Related Threads: Available as an addon called: Similar Thread for Xenforo and View More Thread Same Subforum
Detect Duplicate Threads: Available as an addon called: Similar Threads Check (Google)
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Abnormal Behavior Detection
Which addons do we have that covers what's missing?
They rated ease of plugin installation very low but Add-On Installer by Chris Deeming solves this.