This is to navigate checkboxes in a window for issue 2712

[RiceCrispyy]

This is to navigate checkboxes in a window using , and fill checkbox with this also highlights the active check box and text using user's chosen theme.
#2712 (comment)

[wipodev]

Thanks for your contribution!
I tested your pull request locally and confirmed that everything works as expected.
I've merged your changes into my fork to keep it updated with your improvements.

Please note that my fork is not the original repository, so this does not mean it is merged into the main project yet.

Your changes are now available in my fork:
Stukk

Great work 👏 and I hope your contribution gets accepted upstream as well!

[FedericoSpada]

Hi,
I like the idea, but you have used CTkButton's specific colors for another widget. You should update all themes to consider a new "highlight_color" within CTkCheckBox settings. Moreover, I would leave the text color unchanged.

Maybe we should also add this feature to all widgets, since once you start pressing "tab", you expect to cycle among all widgets on screen.