Installed this plugin and a few hours later MalwareBytes flagged it as adware. Deleted it.

Edit: Just realized it doesn't show ANY plugins. At least it shows the theme so I'll leave it at 3 stars, but should really be 2.5 since it only does exactly half (2.5/5) of what it says it does.

Not perfect on showing plugins, but for basic data as a web developer trying to see info a site is using, it fits the job.

Działa wyśmienicie :)

Thanks developer this extension that it's compatible with Firefox 57+.

i really like this..thanks

EDIT: After changing to the 64-Bit Version of Firefox, the Addon worked again.

Original:
The Addon does not work on my Firefox Browser (Version 51.0.1 - 32-Bit). Just a blank-site is popping up. Dont know why and what the solution is.

Was working fine, but suddenly all I get is an empty tooltip - maybe related to recent FireFox update?

So far, so good. The addon has detected the themes used on all of the WordPress websites I've browsed so far since adding it and most of the plugins used on each too. A free WP detector addon for Firefox has been long overdue. Thank you James for delivering one!

Detects Theme - not Plugin