I've had this problem for a very long time now and have not been able to find anything about it anywhere. Whenever I have a break point in a collision event for an object (example: my collectible object has a collision event that when it collides with a player it is gotten by them) it doesn't appear in the debugger. The debugger still stops and walks through the code as normal, the variables update correctly and stuff, but I just can't see it happening. It doesn't ever open the collision event's code in the debugger window and there's no little red bar on the line it's on (because the line it's on isn't on the screen anywhere). As soon as the code exits the collision event, it pulls up the next event correctly and everything works fine, but if it ever goes back into the collision event, it just leaves open whatever the last event was before the collision event and doesn't show any new code until exiting the collision event again. This has been happening for quite some time now for me, pretty much since I got GMS2. It's a very annoying glitch and I can't seem to find any info on it. It has persisted through multiple updates and I can't figure out why. It is more difficult to debug collisions when I can't see what's going on in them. If anyone has any tips that would be very helpful.