Provide intellisense in rehosted designer scenario
Intellisense should work automatically against C# and VB expressions but also allow hooks for other expression languages.
This can be done using Roslyn and a code completion library like AvalonEdit. See this blog post for more information: https://blogs.msdn.microsoft.com/workflowteam/2016/07/20/building-c-expressions-support-and-intellisense-in-the-rehosted-workflow-designer/
Mehran Davoudi commented
Our team is waiting for this feature. Despite there's some hacks to do this.