Getting the refactor menu on a class operator (e.g. "bool operator==(const MyClass& other) const") freezes Qt Creator for several seconds.
This  happens when  when opening the regular context menu on top of an operator which does not yet have an implementation.

To reproduce just add following in a large project header file.

bool operator==(const QWidgetData& other) const;

Then place cursor somewhere in operator and hit Alt+Enter. a context menu will appear but after a while then once popup menu is visible hit enter again to choose default option that also takes a while to write the definition of the function.

If this is not any operator function but just regular member function like foo() then this whole operation is quick.

Attached is screen recording
It is possible that this is related to the project size, and therefore may not be reproducible in a small test project.