just tried 1.81 over an area & it seems the profile tool is ignoring the settings units (meters) & reporting data in feet.
this area's elevation ranges from 473m to 598m, avg 530m, really looks like the tool is using feet.
the mouse over bits report the correct elevation. looking at the other interactive tools, seems they all use feet instead of meters for elevation.
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Hi Paul
Something's amiss with your settings.
I took a look at the same area and my profile graph differs in terms of reporting elevation units.
Can you confirm that your elevation units are set to "meters" under the Settings menu?