Major bug with aimed spells
I made a post about this before but it seems like it didn't get attention and to make things worst the bug is starting to happen more frequently.
At random times when firing a free aim spell (Any spell that doesn't require you to target a unit) the spell will fire backwards, opposite of the direction of where ever you're aiming. If the spell is something like flash with the ability to set the range based on your cursor then it'll simply activate it at almost 0 range which looks like the person flashed in place.
I can only recall 1 source off the top of my head but I've been seeing this in so many videos happening and some of the players aren't noticing it and writing it off as maybe a misclick.
Personally this is happening on a daily basis and it even happened twice in a ranked game with gnar where my ult fired backwards and my flash went off in place.