I was like "oh common, that can't be a real comment, it's obvious to everyone how unstable this still is", then I saw that the comment was from Arathorn.

You know, for half of the time you spend commenting over here to save face (or something), you could work with your users and see their firsthand experience for yourself.

Lol, messages showing up randomly days later is par for the course for our tiny group chat, most of whom are on matrix.org. Sometimes element won't download messages for some rooms (or even all rooms) for days/hours. Matrix has gotten far less reliable over the years (and I used to run a few homeservers).