Does the forum logs give an error when it crashes?
Do you have mongo and nginx logs on?
There should be some useful information in one of the logs as to what is happening.
Auto size of the preview windows needs some kind of intelligent restrictions...
This is already reported here https://github.com/NodeBB/NodeBB/issues/5208
@baris said in Composer preview auto size issue:
This is already reported here https://github.com/NodeBB/NodeBB/issues/5208
Cool