Issue sideloading the BromiteSystemWebviewOverlay.zip file using adb

[Kaimeeno]

So I am running LineageOS 20 on my galaxy s9 which is rooted with magisk v27. Whenever i try an follow the instructions saying to install it using the following command adb sideload BromiteSystemWebViewOverlay.zip while in recovery mod., I get the following error

ERROR: recovery: footer is wrong
Update package verification took 0.2s (result 1)
ERROR: recovery: error: 21
installing update
ERROR: recovery: Error in /sideload/package.zip

Install completed with status 1
Installation aborted

Oh and I make sure to press "yes" when it says signature verification failed. I am really not sure what I'm doing wrong. The only things I can think of is that the guide mentions that this has only been teste for LineageOS 19.1 and android 12, while I' using LineageOS 20 and android 13.