UI stuck on a big database

On a self-hosted database with >66000 rows total, when trying to access the UI, I get a blank page:

On the server, ps aux | grep node shows a process that uses 100% of the cpu:

root     2569920 99.6  0.5 976512 129536 ?       Sl   19:00  30:09 node _build/stubs/app/server/server.js

What is weird is that sometimes, after restarting grist 2 - 3 times, it works again.

Is there a way to know where it “hangs”, so that I can try to fix the problem?

Solved by the yarn command described here