I have ported patches from 975 to 2019.2 and noticed some things not working quite right even though no errors are reported.
When going into the patches, I’ve noticed some nodes are greyed out as if the type is uknown - even though they are not generic nodes and are defined.
For instance in Schema.UI.2019.2c.vl GridLayer
After opening the patch containing the operation (SchematicViewContext) I can see more greyed out nodes but after less than a second everything becomes normal and the correct functionality returns.
Sidenote: The current state of the editor gets reflected in export, eg. before opening patch the export has the same error, after opening and exporting the error is gone.