UCs require high school transcript for transfer?

I got an email from my community college and it mentioned that UCs need high school transcripts too. I was really confused at first thinking “why would they possibly want that” and i look on the UC website and it says this

“You will be asked to submit official transcripts from all schools and colleges you have attended, including high school, regardless of your length of attendance or whether you believe the credit is transferable. Some campuses may request transcripts prior to admission.”

Does this actually apply to someone going from community college to a UC? I did TERRIBLE in high school, i had a 2.0 gpa with at least 10 Fs and Ds. Im going to be applying with a 3.6-3.7 college gpa for junior year

Will high school seriously matter? This seriously bothers me, its already so competitive, and my high school transcripts are so bad they might panic when they see it and immediately reject me.

They don’t care about high school grades as a transfer. They just want to confirm that you graduated like you said you graduated.