I’ve tested the latest release candidates of GeneratePress theme, PG Premium and GenerateBlocks on my Dev environment. I encountered the following bug: using the new color palette does not work consistently correct. For example, when I want to select a color from the palette to create a global style the variable is not applied. This happens on different occasions.
I have tried this Safari and Chrome (latest version on Mac). WordPress is on the latest version.
It shows that I cannot use the new color palette in the block editor with the current release candidates GeneratePressVersion: 3.1.0-rc.1, GP Premium Version 2.1.0-rc.1, Generateblocks Version 1.1.0-rc.1.
If you have further questions, don’t hesitate to ask.