Hi Juliet, maybe this will help. A small extract here or the link
below for the full reading.

HOW TO TAKE A SCREENSHOT IN MACOS MOJAVE

        Many of us have long been familiar with the old standbys of macOS
screenshots:

        * _Command-Shift-3_ takes a screenshot of the entire screen, which
immediately saves to the desktop.
        * _Command-Shift-4_ takes a screenshot of a specific area, which you
select by dragging an adjustable rectangle.

        But with Mojave, we also get _Command-Shift-5_. Use this, and
you’ll get a small menu bar along the bottom that offers five
choices. (If you use a MacBook Pro with a Touch Bar, you’ll also see
these options on the bar.) Those choices are:

        * Screenshot the whole screen (exactly like _Command-Shift-3_)
        * Screenshot a specific window
        * Screenshot a specific area (exactly like _Command-Shift-4_)
        * Record the entire screen (for video)
        * Record a specific part of the screen (for video)

On the right side of the bar, you’ll also see an _Options_ menu
that lets you further customize your screenshotting experience.
Importantly, these options can also change how screenshots behave with
good ol’ _Command-Shift-3_ and _Command-Shift-4_.
 
https://www.macworld.com/article/3286528/article.html [1]

Kind Regards

Peter Crisp

----- Original Message -----
From: wamug@wamug.org.au
To:"WAMUG Mailing List" 
Cc:
Sent:Thu, 6 Feb 2020 18:02:49 +1100
Subject:Screen problem

HelloFor some unknown reason when I do a screen capture Shift command
5 I am left with a bright area when the capture was done and the rest
of the screen darkened, the only way to clear is to do a
reset.Mojave 10.14.6Imac 21" late 2013regards Bill 

Links:
------
[1] https://www.macworld.com/article/3286528/article.html

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