We don't really see, and it is meant to be ambiguous to keep the audience and the characters in suspense. It is presumed the bleach was used.
đș "The North remembers"
I thought she drank bleach. Honestly I'm not sure. At some point, it looked like someone else was in the room with her and walked out when she fell over. What was up with the mirror?
A bit of the old ultraviolence...
I know. I didn't even see a mirror.
Don't hate on contrarians
I think the mirror was the thing that looked a bit like a washing machine.
http://youtu.be/GAIJ3Rh5Qxs
The mirror was behind her on the wardrobe It's not obvious though.
The washing machine was a washing machine. Although the drum did go black for some reason.
Her agent booked her for Unfriended 2 and 3.
shareThat's what I think.
Please excuse my terrible redaction, english is not my native language