EEXCESS visualisation widgets are JavaScript based visualisations for cultural heritage and scholarly content. The widgets are used in the different EEXCESS clients, like the Chrome Extension. They are typically iframes and therefore self-contained.
When a filter is selected (e.g. 'audio'), new results arrive and those do not contain audio results, the filter button is not shown to the user, but still active. In such cases, the filtering should be reset to 'show all'. Or instead a notification might be shown, that no audio results are available for the current result set with a hint, that the user should switch to one of the available filters, whatever you prefer.
When a filter is selected (e.g. 'audio'), new results arrive and those do not contain audio results, the filter button is not shown to the user, but still active. In such cases, the filtering should be reset to 'show all'. Or instead a notification might be shown, that no audio results are available for the current result set with a hint, that the user should switch to one of the available filters, whatever you prefer.