Polymarket's price WebSocket can stall while connected (and the docs won't warn you)

Polymarket’s RTDS price WebSocket may reject the documented symbol filter or return no data.

The socket can also stay open while silently stalling, leaving clients with stale prices.

Recommended workaround: subscribe without server-side symbol filters, filter messages locally, and track last-message time to reconnect on silence.

This matters for trading bots and apps that rely on Polymarket’s live feed to avoid missed updates.