@Javier SendraGlobally hide the filtericon on all dashboards:
Set visibility to hidden for the class .widgetIcons or .dataWidgetFilters. You can overwrite any CSS rules by uploading a theme that holds the perspective common.
Hide the icon in just one dashboard:
Use a custom visualization - with javascript inside that visualization you can hide the filter icon visibility.
In the globalTheme you can also upload javaScript which is loaded any time you hit the portal. Inside that you could identify any start of dashboard and then dynamically disable the icon according to programatic rules like username, group belonging to, dashboard name ....
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Ralf Roeber
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