z-index issue with modal in gutenberg

Hi,

I found this bug too and the problem is that Gutenberg uses an element with fixed position to attach the editor on screen. The ACF meta box is rendered inside this element and two elements with position fixed can’t exists together, they cause z-index conflicts on the browser render.

Sorry to say, but I still don’t know how to fix this without asking the Gutenberg team to not use that fixed element in the editor.

A suggestion, you could use ACF Blocks to replace the Flexible Field feature and instead of creating layouts, you create blocks. That’s what I done since I migrated to Gutenberg and it works exactly the same way to build pages.