i am a victim of this too. Realized the other while filling it up. i have several on the back hatch. All are bubbling from under the paint. Made my inspection apt with the dealer on monday the 27th. Ill report back!
post a picture of this paint failure .
many different types of paint failures posted so many different reasons.
if the paint surface is smooth and shines perfectly but the paint has a bubble then this can be from 1,defective metal 2,contaminated metal surface,3 paint was not properly mixed/primer coat.
if the paint is stained and bubbles up this can be from iron dust, acid, chemicals etc..
iron dust does eat at the clear coat. the lift gate does collect lots of road crap.. some of the crap is iron dust from your brake pads.
so the lift gate does require frequent washing of the paint and applying a paint sealer/wax protection . using an acid cleaner [car wash] will do it . use car soap designed for paint finish avoid any household cleaners like dish soap and other cleaners that have acid.
I have inhaled much rail dust over 25 plus years cause I worked in it.
a properly cleaned paint surface and a wax coating protects from environment damage.
on the metal contamination that is a Toyota defect where the painters did not properly prep the metal or the metal itself is with defects ..
rust blisters back in the 1970's with GM was on 110% of all the vehicles produced .this was a sheet metal defect . metal rusted from within the sheet metal . it rusted inside and outside of the defective metal so rear fender had rust blister it would rust inside the trunk and on the outside of trunk.
on Toyota I have seen many red and black with the clear coat peeling off..