Symptoms of Flexgate
MacBook Pro models impacted by the “Flexgate” issue experience a number of significant problems related to the display’s backlight, according to user reports and a diagnostic teardown by iFixit.
Most notably, users report a strange, warped “stage light” effect at the bottom of the MacBook Pro’s display when it’s set to high brightness. This seems to be the most common symptom.
In some cases, other users report that the backlight on their MacBook Pro devices can simply shutdown if the lid is opened above a certain angle. According to iFixit, this can occur is the lid is opened more than around 40°.