Annoying IntelliSense behavior with multiply defined variables (18.3.0 Insiders [11109.51.main] but probably also 17.14)

IntelliSense doesn't list ambiguous variables (e.g. variables that are multiply defined) leading to some unfortunate behavior if quickly type something followed by expecting the variable.

I am rewriting this function to add “double width” to the parameter list. Note this causes an error on line 90 – since I define a local variable of that name there – but there is no indication of an error on line 73.

I then – on line 83 – type “if (wid” expecting to get the width parameter but instead – before the tab – I get this, so tab selects CaretWidthOption. Imagine how confusing this is if I’m working in a larger function.
My expectation is that things like IntelliSense would use the preceding definition of width rather than suppressing it entirely because there’s an error or ambiguity.

The issue names no source file, test, or entry point. Start by reproducing C# IntelliSense completion for a multiply defined local and parameter named width in the reported Roslyn/Visual Studio versions, then trace the completion path; done means the preceding definition remains available and Tab selects it instead of an unrelated suggestion.

Written by the indexing model from the issue text.