REG: "Clean whitespace" no longer works as of 4.13

The explicit "Clean whitespace" feature (either via Edit menu or shortcut) no longer works in Creator 4.13. It definitely still worked in 4.12 versions.

Steps to repeat:
1) Configure "Spaces only" under "Text editor" - "Behavior"
2) Open a Qt example with c++ source code of your choice
3) Open one of the source files in an external text editor
4) Enter several tabs into a blank line
5) Open the same source file in Qt Creator
6) Select the whole source file "Select all and "Clean whitespace" via Edit->Advanced
And Nothing happens