The MIT license says:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
In case of proprietary software, there is usually a dedicated screen which one can navigate to and view all such notices.
But what about cases where we design a device with very limited user interface, not suitable to display the license and use an MIT-licensed library as part of the firmware.
Would including the notice in the manual be enough, provided we ship the manual with each unit? Or even adding a license leaflet, separate from the manual, which is shipped with each unit?
Separately, what about firmware updates? For example, we digitally ship an update (potentially changing included libraries), would having a license file accompany it be enough?