Click the "Show more" button below the video description to see the tags.
--------------------------------------------------------- Not working for you? Troubleshooting tips: ---------------------------------------------------------
(1/3) Make sure to completely reload (F5) any YouTube™ browser tabs you had open before installation.
(2/3) Make sure the YouTube™ videos you viewed actually have tags. Try a few other channels. Some videos simply don't have tags.
(3/3) Make sure you don't have any conflicting extensions, user scripts, styles, etc. that modify the YouTube™ website.
If that doesn't help, leave a message in the support tab. If you do, *please* make it clear that you've tried the above, or I'll just refer you back here :-)
=================================== Permission info ===================================
The permission "Read and change your data on all youtube.com sites" is needed to obtain and display the video tags, and is used for that purpose only.