With all new Fire TV models, there are always people wondering if anything has been done to thwart sideloading apps and, thankfully, it’s all business as usual with the 3rd-gen Fire TV Cube. Developer options are present and behave just as they do on other Fire TV models, although, as you’d expect, they follow the new behavior where developer options are initially hidden and must be revealed. My Downloader app works just fine and you can enable the option to allow it to install unknown apps just fine and use it to sideload APKs on the Fire TV Cube 3. My button remapping utility also works fine to remap the app shortcut buttons of the Fire TV Cube’s remote. However, everything isn’t perfect because there is one old sideloading issue that has resurfaced on the new Cube.
The really old bug where some sideload apps have missing or broken icons is, unfortunately, present on the new Fire TV Cube. This is really strange because, after over a year of ignoring the issue, Amazon finally fixed this bug a couple of months ago. Fortunately, it doesn’t affect all sideloaded apps. Just the ones that store their icon image a certain way.
Even though I’ve made sure to install all OS and system component updates, I have noticed that some of the system apps on the new Fire TV Cube are older than the ones on my other Fire TV devices, like the 2nd-gen Cube or Fire TV Stick 4K Max, where this bug isn’t present anymore. The Fire TV Home Launcher version on the new Cube, where I assumed this bug lived, also seems up to date and matches the version on my older Fire OS 7 devices. Hopefully, it’s just a matter of some newer system app not being pushed yet to the new Cube which is causing this issue to reemerge and it will be fixed soon.