This is what I saw for years during the visual migraines I had for years.machineslikeus.com/sites/default/files/users/NLN/migrain-2.jpgi.ytimg.com/vi/fo139jYAFzA/0.jpg
In the second example, the colors weren't that bright, but they were in the more jagged shapes as these.
These are what are known as a scintillating scotoma, or translated into humanese, it means a colorful blindspot.
There are a variety of migraine symptoms, mine were strictly visual, no headache. Others get these as an aura before a headache.
If you're interested in reading about
the range of migraines, this book may be of interest. It's written by Neurologist Oliver Sacks and is done for understanding by non-professionals. /en.m.wikipedia.org/wiki/Migraine_(book)
Whenever someone experiences these symptoms for the first time, you should see a doctor to rule-out any other physical issues, but migraines can indeed produce a broad range of symptoms.