No matter how many times I tried I couldn’t get the LastPass binary component to show as working in Safari on my Mac. Even after reinstalling the latest version of LastPass (as of August 2018) numerous times I couldn’t get the binary component for Safari working. Clicking the LastPass toolbar icon -> ‘More Options’ -> ‘About LastPass’ confirms the binary component wasn’t loading (Will show false instead of true, as I just fixed mine).
I did find a post that reported a fix for this issue, however the linked fix was only documented in a set of images that are currently broken (not helpful). Luckily there is a web archive that contains a snapshot of the images, however I’ll document the simple fix here also for future reference.
Editing the Lastpass plist file
Using Finder navigate to the hidden folder (Finder shortcut = shift + cmd + g)
Open the com.lastpass.LastPassHelper.plist in a text editor (Needs admin privileges IIRC) and change the ‘Program’ entry that contains “REPLACE_HOME/Library/Application..” to reflect your Mac OS account’s username (which should be the same as your users home directory, e.g dan).
Checking the about page again should result in a working binary component.