Repro: keep adding images to a board and eventually when manipulating images, the tab will refresh and it'll show This happens in macOS on Chrome at least, even with plenty of RAM.
This makes it hard to keep expanding a board, necessitating the switch to a second board, which defeats the purpose of organizing everything together.
Three days ago support said "I've shared this info with my team. We're working to fix it now." but I've reported it, in case anyone else is still seeing it.