Your data are not transmitted
'As Custom Visuals' do not send your data to anywhere. Your data means here the data you provide to the visual in order to visualize it. Custom visuals receive data from Power BI Framework and render UI based on those data; our custom visuals do not send your data to anywhere else or use your data in any other way.
Personal information is not collected
Our custom visuals do not collect personal information.
'As Custom Visuals' can (and most probably will, however some data are collected by sampling, so not from everyone) collect anonymous information about usage. This information can (and hopefully will) be used to improve the visuals or to create new products or services.
Data collected can contain for example settings used, size of visual, timing of load and render times , features used, and similar information about usage and usage conditions. Person, device, site or even single installation cannot be identified from this data.
Data is not shared with any third party except when needed for the processing of the data. Data is not given or sold to third party except if the intellectual rights of the visuals are transferred.
In order to develop better visuals, I need to know how they are used. I'm not interested in the data you are processing.