Stall block polling bootstrap when the network is down (#3924).

src.ts/providers/subscriber-polling.ts

@@ -50,7 +50,10 @@ export class PollingBlockSubscriber implements Subscriber {
     set pollingInterval(value: number) { this.#interval = value; }
 
     async #poll(): Promise<void> {
+        try {
             const blockNumber = await this.#provider.getBlockNumber();
+
+            // Bootstrap poll to setup our initial block number
             if (this.#blockNumber === -2) {
                 this.#blockNumber = blockNumber;
                 return;
@@ -69,6 +72,12 @@ export class PollingBlockSubscriber implements Subscriber {
                 this.#blockNumber = blockNumber;
             }
 
+        } catch (error) {
+            // @TODO: Minor bump, add an "error" event to let subscribers
+            //        know things went awry.
+            //console.log(error);
+        }
+
         // We have been stopped
         if (this.#poller == null) { return; }