"The Pfizer-BioNTech COVID-19 vaccine for children ages 5 through 11 also contains a different buffer."
Source: https://www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/covid-19-vaccines-for-kids/art-20513332

So there IS at least one confirmed difference in the formulas. I'm interested to know which buffer they are adding to the pediatric injections. Does it have any potential unwanted effects? What outcomes might different buffering have? Are there any other differences in the formulas?