Canon continues to apply for a multitude of patents dealing with stacked sensors.
This patent is for new ways of interconnecting the sensor and the processing chips together using lapped pads between the two substrates (one for sensor, the other for processing).
We saw something like this when Canon was researching ADC's to put on their sensors, where the R&D departments within Canon spent a considerable amount of time and money applying for applicable patents.
Whether or not this is a sign of things to come photography, or whether or not this will more apply for high speed 4 and 8K video applications, is anyone's guess right now. Both stills and video could use stacked sensors to improve ISO and DR response not to mention speed up processing.
Japan Patent Application 2018-006561