Investigate Collaboration with Vietnam Diff

The `html_diff_render` diff of this change seems *way* too extreme, highlighting almost the whole page even when many chunks of text are the same. Investigate what’s going on and see if there’s anything obvious we could fix:

https://monitoring.envirodatagov.org/page/ef6c651c-2e33-4a4a-a5b4-16e9c42535de/d5089964-7af5-4353-8b3d-e7eb9199de26..5f040609-c4f6-4eb9-ac86-89ee074556cd