Counter-intuitively, cameras connected to HikVision can be renamed by following the menus Configuration→Image→OSD Settings and entering the name of the camera in the Camera Name field. Even though, the settings appear to be just for OSD, the setting is made for the entire NVR.

Long story short: use the Pale Moon browser.

Some HikVision NVRs are still using NAPI plugins that are not compatible with most modern browsers. Pale Moon is a firefox fork that still supports NAPI plugins such as flash.