Trailing return type of nested template breaks indentation

Code like this breaks Creator's indentation:

auto foo() -> std::vector<std::tuple<int, int, int>>

After pressing enter, the indent is placed way over to the right. The part that seems to be confusing the editor is the ">>", since putting a space in-between prevents it from happening.

Enabling the clang format plugin indeed fixes the issue. However, I had explicitly disabled that plugin because enabling it causes a major slowdown while editing big source files that contain tens of thousands of lines. Pressing enter for example to add a new line takes 5 seconds, which makes that plugin completely unusable as editing code with this kind of delay makes writing code impossible.