Modpack version
1.81a

Issue
Whenever I press any key in the inventory, everything shifts upwards by one row. The same happens upon release of the key.

You need to bind some None buttons (machine translation

Either delete the options.txt file in your instance, or bind the Cyclic move inventory up/down buttons to some keys that are not media keys, both should fix it. Please let us know if it doesn't :)

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