We have an expand/collapse mediums switch on releases with many media (like https://musicbrainz.org/release/d4e093c5-6aea-4c3d-942b-d0f83d6bf05d) - but there's no equivalent inside the RE. For example, to change a credit on all discs, you need to click on every single arrow to load the disc. There should be an option to expand all discs here too.