Tk will not respond to changes -- caused by the program or external factors like screen changes -- unless you enter MainLoop.

See the POD examples for the details.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
With the rise and rise of

In reply to Re: Perl/Tk window contents disappear when obscured then revealed by BrowserUk
in thread Perl/Tk window contents disappear when obscured then revealed by Another Ed

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