For anyone having the same issue but the above doesn't work, you may have extensions disabled.
In an older version of safari there was an option in the developer menu to disable extensions, I had previously clicked this option and forgot. I have later updated my OS/Safari and the option disappeared from the developer menu but it turns out the setting remained.
To change the setting you can:
Manually update the plist file.
Open the plist file in Xcode found at "~/Library/Containers/com.apple.Safari/Data/Library/Preferences/com.apple.Safari.plist"
and set the property "ExtensionsEnabled" to "YES" (mine was set to no).
OR
Use the Defaults Command
defaults write com.apple.Safari "ExtensionsEnabled" -bool "false"
I then re-opened safari and my extensions now showed up in the safari Settings
I hope this helps anyone having the same issue.
Andy_Prtt
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
Post
Replies
Boosts
Views
Activity
In my haste of posting I have incorrectly typed the boolean value
defaults write com.apple.Safari "ExtensionsEnabled" -bool "false"
it should be:
defaults write com.apple.Safari "ExtensionsEnabled" -bool "true"