when typing a function name directly (without spaces) after an operator which is not a “standard operator” (e.g., +, -, *, /, ^, =) auto completion does not work.
This applies both to built-in operators (e.g., ÷, ⊻, ∈, ≈) as well as user defined operators (e.g., ⊕, ⊗)
This sounds like it shod be a Github issue.