More info. It seems to only impact initial load.
I’ve had to exit chrome to reproduce again.
Exit Chrome
Reopen
Navigate to Meta
Navigate to topic
Reply to Topic
Enter a line or 3 of text
Click title
Scroll to bottom quickly
Click text box to focus on reply
Offset occurs
To fix:
Navigate away from topic (latest)
Refresh page (composer should disappear)
Navigate to topic (composer restores)
Hit reply
Once it is fixed I can’t get it to happen without closing chrome. It seems something in the initial setup of composer is causing this. Not sure what though.