allow suffix of underscores for words (notably keywords), similar to semantic completion;
allow suffix of underscores for words (notably keywords), similar to semantic completion;

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle