Symbols not found in Intellisense once an error occurred

I think if found an error but are not sure if the erroneous device is located in front of the screen.

VS 2017
Elements 9.1.99.2151
Oxygene

I started an Island test drive.

  1. When I open the solution everything works fine.
  2. I type into the Editor and get all suggestions (Intellisense (I think))
    (Screenshot)

  1. Once a syntax error occurs for example no symbols exported from the RTL or the Island libraries are presented anymore in Intellisense

  1. When I open the solution again everything works well but VS presents some errors

These ‘errors’ do not seem to have any impact. Visual issue.
4.1) for a few seconds - once compiled with an error the symbols can no longer be found in Intellisense

(*
This ‘bug’ reminds me of a special situation in Fire on the Mac when I create a library for example and include it into a project. In that case adding and removing an empty project helps (Issue with automatic saving). Once the project file or ‘solution’ is saved everything works fine there.
*)

Sorry for the screenshots. The ‘suggestions’ disappear during the screenshot.

I did not run into this problem in a .net project or jvm project.

The compiler knows the symbols. Compilation works at any time.

Do I have to include the source code of the libraries?

Am I doing something wrong?

Edit: The situation seems pretty similar to the behavior of the ‘Intelliisense’ in case of an error. In case of the JVM or .net after successful compilation the symbols return. I’m very happy if Water helps to free us from the VS.