kivy request dialog: follow-up c95791d7ee

related https://github.com/spesmilo/electrum/pull/7929

electrum/gui/kivy/uix/dialogs/request_dialog.py

@@ -172,9 +172,6 @@ class RequestDialog(Factory.Popup):
             qr_data = qr_data.upper()
         if qr_data:
             self.ids.qr.set_data(qr_data)
-            self.ids.qr.opacity = 1
-        else:
-            self.ids.qr.opacity = 0
         if not qr_data and self.error_text:
             self.show_text = True
         else:

electrum/wallet.py

@@ -2847,7 +2847,7 @@ class Abstract_Wallet(ABC, Logger, EventListener):
         if status == PR_EXPIRED:
             address_help = URI_help = ln_help = _('This request has expired')
 
-        is_amt_too_small_for_onchain = amount_sat < self.dust_threshold()
+        is_amt_too_small_for_onchain = amount_sat and amount_sat < self.dust_threshold()
         if not addr:
             address_is_error = True
             address_help = _('This request cannot be paid on-chain')