Save button fix with Usage dialog popup

[OmkarSarkar204]

Follow-up PR of #1268.

Issue Still persists on new users on the Save and start configuration button.

Fix #1264

[amilcarlucas]

This fix does a lot of changes, and it creates the risk of regressions on Windows and Linux.
Can you try to minimize the changes to the existing code?

[OmkarSarkar204]

It's quite tricky, i tried many ways by adding, removing the grabset() but the button is still unresponsive, the main reason visibe is the "guidance popups" not showin before every new page.
I think, while the window calculates its position right now, it's accidentally allowing background processes to interrupt the UI while it's still trying to draw the window, which is what causing the issue.

Im thinking of blocking those interruptions by swapping update() for update_idletasks(), and ensure the grab_set() skip is strictly isolated to macOS.

[OmkarSarkar204]

@amilcarlucas, Can you please take a look at it if its ok now?

[OmkarSarkar204]

Hello @amilcarlucas , I resolved the merge conflict to update with the master branch. Tested it locally and also updated the test. Its working.

[amilcarlucas]

Thanks for continuing to work on this.
I do not like the amount of code that this PR adds. But I will review it this weekend. Thanks.

[amilcarlucas]

Closed in favor of the much simpler #1332