[accelerator] auto scroll when clicking on "Accelerate" CTA

frontend/src/app/components/accelerate-checkout/accelerate-checkout.component.ts

@@ -223,6 +223,7 @@ export class AccelerateCheckout implements OnInit, OnDestroy {
       this.loadingBtcpayInvoice = true;
       this.invoice = null;
       this.requestBTCPayInvoice();
+      this.scrollToElementWithTimeout('acceleratePreviewAnchor', 'start', 100);
     } else if (this._step === 'cashapp' && this.cashappEnabled) {
       this.loadingCashapp = true;
       this.setupSquare();