I did have a bonus round a while back on 40p where I had four expanding wilds filling the screen. I was happy with the first two but they kept getting added, so I did accumulate a nice win out of it.
When I had the first four reels filled with the wild I was sure the fifth would come so I stumbled onto the Prt Screen button; unbeknownst to me I had a banking app running so it wouldn't capture the screenshot, instead it crashed the bloody game!
Needless to say when I reloaded the game hoping for that 5th reel wild it never came, I'll never know how that round would have truly played out. It seemed like I'd be there all night with them harps popping up. Still got over £200 from it but I fear that will never be repeated