With my highest possible screen resolution set at 1280 X 1024 X 32, I normally reduce all my screen shots, photos, etc, to a maximum of 900 Pixels wide to prevent having to scroll the Thread window sideways to view the contents of the whole page,
including all text.
The increased width of the margins in the latest versions of the YaBB Forum page reduces the available width of the page for screen shots, photographs, etc!
One of the reasons why I don/t spend too much time browsing the Screen Shot threads!...

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Flying Trucker's screen shots at 800 Pixels wide fit my screen perfectly, and include all its text!...

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Paul...

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Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.