"Show VCA items" is a function which works in Internet Explorer 11 with the Bosch MPEG ActiveX installed. Due the end-of-life of Internet Explorer, this function is no longer available on Microsoft Edge.
For bullet and dome cameras the clear window / bubble is generally made out of polycarbonate with a special hard coating to provide scratch resistance.
Please note that this recommendation might help, but cannot guarantee the high quality of the image. It depends on the camera FoV and the environment where the camera is installed.
In case you have noticed a gap between the left and right of the lens installation, this might cause improperly focus for the camera's image.
Therefore, please proceed as explained in this article.