The error message when viewed from JS Console looks like this:
This occurs when ‘Use Advanced Matching’ is used for Facebook pixel. This adds an extra line:
em: ‘insert_email_variable,’ to the FaceBook Pixel.
=> We’ll update the GTM container soon so this update won’t be needed anymore.
HOW TO FIX THE ERROR
Step 1: Login into your GTM Container than follow the steps as shown here:
Step 2:
Step 3:
Step 4:
Step 5:
Step 6:
Step 7:
Step 8:
PLEASE RETEST and MAKE SURE THE ERROR NO LONGER APPEARS