HtmlGenerator::generateCompactList() uses an algorithm to find out a common prefix for classes/qml types when generating the alphabetical lists. It's restricted (assumes a single-character prefix) and somewhat useless for Qt.

This algorithm should be either

• Replaced with hardcoded 'Q' prefix for C++ classes, and empty prefix for QML types
• Replaced with qdoc config parameter(s) for prefix string(s).