Originally from Causese's WA.
WA requires this addon to work properly (otherwise the sounds won't work): https://www.curseforge.com/wow/addons/dementiasharedmedia
Video-example: https://www.youtube.com/watch?v=8XB-XbyyfvY
Similar WA (lines on the borders of screen for bomb timings): https://wago.io/VNHxvukb_