Hi Howster,
If you install the “ExpressionEngine Pro” add-on from your add-ons section, you will then have a gear in the top right corner, and you can click the eye next to a given dashboard item to hide it.
Please note, Pro is a paid add-on, for a site that is live.
Some people also use https://expressionengine.com/add-ons/mx-cp-css-js However as things change in development you may have to update your JS and CSS as a whole to hide it accordingly.
Thanks,
-Tom Jaeger
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