What is the Facebook Link Shim?
The Facebook Link Shim helps protect the identity of the user clicking through on a link to the destination landing page.
The Facebook Link Shim can be identified in Google Analytics and Statistical Reporting as l.facebook.com / referral and lm.facebook.com / referral (mobile).
It helps Protect Privacy and Identity of the end user. It also strips valuable marketing and referral data from statistical reporting.
NOTE: It should be mentioned and clarified for many people using Google Analytics and many other statistical reporting tools that before introducing the Facebook Link Shim being identified as l.facebook.com / referral and lm.facebook.com / referral your statistics may have classified this traffic under Unknown or No Referrer or No Referral Data, Etc.
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