Once again reset completion model first time tab is pressed. This ensures we never tab the wrong username, but it's really expensive.

src/widgets/helper/resizingtextedit.cpp

@@ -101,6 +101,7 @@ void ResizingTextEdit::keyPressEvent(QKeyEvent *event)
 
         if (!this->completionInProgress) {
             // First type pressing tab after modifying a message, we refresh our completion model
+            this->completer->setModel(completionModel);
             completionModel->refresh();
             this->completionInProgress = true;
             this->completer->setCompletionPrefix(currentCompletionPrefix);