I am developing code completion in my plugin.
The CompletionProvider is being called as expected, and LookupElements are added to the CompletionResultSet.
However, no results are displayed to the user.
I debugged the code completion process and found, that in CodeCompletionHandlerBase.completionFinished a list of LookupElements is retrieved from the indicator.
This happens after the code completion.
However, this list is somehow empty.
I have only one CompletionProvider yet, and can observe that LookupElements are added to the CompletionResultSet.
I know, that there are several other completion contributors provided by the IDE, but what are possible cases, that the list of LookupElements is cleared?