What is this magnification box in :LR Classic
How did this box get there, and how do I get rid of it? Thanks.
How did this box get there, and how do I get rid of it? Thanks.
It looks very much like the [Guided Upright Tool] in the Transform panel available by clicking the hash icon, or keyboard [Shift+T]

However your screen-clip indidates the tool is not active as the hash icon is visible (the icon goes to a grey dot when active) and yet you continue to see the square box on screen.
There may be a glitch (very technical term) in your graphics card, so things to try might include-
A restart of LrC. A computer restart. An update for your graphics driver. A reset of the Preferences file. Or even a re-install of LrC.
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