🐛 Libraries attached to content block fields are not included in the editor Fixed improved content block rendering by using Drupal's AJAX APIs but has a side-effect of rendering those blocks using whatever the active theme is on the Gutenberg editor page. In most cases this will be people's admin themes. But generally your Gutenberg blocks are themed in the default / frontend theme. So if you had any template overrides or preprocessing in your default theme, they won't be applied anymore for inline content blocks in Gutenberg (note that blocks in the Custom Block library do still render properly).
This is assuming you have an admin theme and it is enabled on the node edit form
Use a custom ThemeNegotiator to force the default theme on the gutenberg.content_block.render route.
MR incoming!
Fixed
3.0
Code
Automatically closed - issue fixed for 2 weeks with no activity.