When asking for help using MuseScore, please use the Support forum, and include as much information as you can. But first, try Help / Revert to Factory Settings, which should fix most issues you might have with controls that have been disabled or hidden for whatever reason.
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When asking for help using MuseScore, please use the Support forum, and include as much information as you can. But first, try Help / Revert to Factory Settings, which should fix most issues you might have with controls that have been disabled or hidden for whatever reason.
Try https://musescore.org/en/handbook/revert-factory-settings
Next time it's better to use the support forum for similar requests:
https://musescore.org/de/forum/52 or https://musescore.org/en/forum/6