I just bought a 8bitdo snes30 controller toplay my retro games and all went well as I paired it immediately and played straight away.
Issues i encountered were when I left the game for some time and the controller went to sleep. I couldnt pair it again (and couldn't get back to libreelec as I couldn't exit retroarch) so had to do a full power down and reboot.
I also noticed that when my TV was off (connected to my rpi3) and I turned it on to play my controller when I powered that on with the start button for 3 seconds wouldn't pair and I had to go to libreelec settings to connect it manually every time.
Finally my issue is that now my TV, when turned off, turns on automatically every few minutes on its own. I clicked the enable standby setting on my controller settings, does that have something to do with it? I assumed that meant I could leave a game paused for a long time and my controller wouldn't power off or lose BT connection ?