Conventional hot keys do not work for hex color field in QColorDialog

Steps to reproduce:

1. In Qt Creator, go to Preferences
2. Click Text Editor on the left pane
3. Choose Font & Colors tab
4. Pick any item in the main colorized list
5. Click on Foreground's colorized rectangle in order to invoke color picker dialog
6. Select RGB Sliders item in a drop-down combo box
7. Click text field on the right of Hex Colour # label to make it receive focus
8. Press Cmd+A to select the current value. Expected behavior: all the text is highlighted with a selection's color. But it is not. Fallback to do that via mouse.
9. Press Cmd+C to copy.
10. Exit Preferences by clicking Cancel buttons.
11. Move focus to text editor.
12. Press Cmd+P to paste. Expected behavior: the hex color value is pasted from previous steps. Actually, some previous text is pasted from the copy-paste buffer. This suggests copying did not work.

Pasting into this text field by Cmd+P does not work either.

PS. A workaround is to use mouse and context menus.