Mathew Newton wrote:
I would've thought it'd be just as easy getting a crowbar underneath
even a closed UPVC window frame - they're not the stiffest of
structures and indeed what with the rubber sealing strips there's
probably enough of an available gap to get the bar into without causing
distortion anyway.

On some models the properly locked position is metal-on-metal, the
draught position is metal-on-plastic.

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