Zoom Feature (undocumented)
I stumbled across an undocumented feature in the zoom options which I found very handy. If you set a custom zoom level then it becomes available in the zoom drop-down list. You can set a custom zoom by simply typing a zoom level into the Zoom% box or in the Preferences dialogue on the Score tab.
This may be obvious but I had missed it.
Comments
Added a mention of this possibility into the handbook at https://musescore.org/en/handbook/3/viewing-and-navigation#zoom