Frosting glass is created by sandblasting or acid etching a sheet glass, which distorts the light to create a blurred effect. To counter this you can stick a piece of sellotape on the frosted glass. The sellotape smooths over the sandblasting turning it back to a transparent window.

Hints

If the glass is frosted on both sides you will need a piece of sellotape both sides.

The deeper the frosting the less effective this trick will be.

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