diff --git a/packages/taler-util/src/bitcoin.test.ts b/packages/taler-util/src/bitcoin.test.ts
new file mode 100644
index 000000000..287cd7e66
--- /dev/null
+++ b/packages/taler-util/src/bitcoin.test.ts
@@ -0,0 +1,53 @@
+/*
+ This file is part of GNU Taler
+ (C) 2018-2019 GNUnet e.V.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ * Type-safe codecs for converting from/to JSON.
+ */
+
+import test from "ava";
+import {
+  generateFakeSegwitAddress,
+} from "./bitcoin.js";
+
+test("generate testnet", (t) => {
+  const { addr1, addr2 } = generateFakeSegwitAddress("B9E0EXNDKGJX7WFAEVZCZXM0R661T66YWD71N7NRFDEWQEV10XSG", "tb1qhxrhccqexg0dv4nltgkuw4fg2ce7muplmjsn0v")
+
+  t.assert(addr1 === "tb1qtfwqwaj6tsrhdtvuyhflr6nklm8ldqxpf0lfjw");
+  t.assert(addr2 === "tb1qmfwqwa5vr5vdac6wr20ts76aewakzpmns40yuf");
+});
+
+test("generate mainnet", (t) => {
+  const { addr1, addr2 } = generateFakeSegwitAddress("B9E0EXNDKGJX7WFAEVZCZXM0R661T66YWD71N7NRFDEWQEV10XSG", "bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq")
+  //bc
+  t.assert(addr1 === "bc1qtfwqwaj6tsrhdtvuyhflr6nklm8ldqxprfy6fa");
+  t.assert(addr2 === "bc1qmfwqwa5vr5vdac6wr20ts76aewakzpmn6n5h86");
+});
+
+test("generate Regtest", (t) => {
+  const { addr1, addr2 } = generateFakeSegwitAddress("B9E0EXNDKGJX7WFAEVZCZXM0R661T66YWD71N7NRFDEWQEV10XSG", "bcrtqhxrhccqexg0dv4nltgkuw4fg2ce7muplmjsn0v")
+
+  t.assert(addr1 === "bcrt1qtfwqwaj6tsrhdtvuyhflr6nklm8ldqxptxxy98");
+  t.assert(addr2 === "bcrt1qmfwqwa5vr5vdac6wr20ts76aewakzpmnjukftq");
+});
+
+
+test("unknown net", (t) => {
+  t.throws(() => {
+    generateFakeSegwitAddress("B9E0EXNDKGJX7WFAEVZCZXM0R661T66YWD71N7NRFDEWQEV10XSG", "abqhxrhccqexg0dv4nltgkuw4fg2ce7muplmjsn0v")
+  })
+
+});
diff --git a/packages/taler-util/src/bitcoin.ts b/packages/taler-util/src/bitcoin.ts
index 0dd83e2db..62d8d8dce 100644
--- a/packages/taler-util/src/bitcoin.ts
+++ b/packages/taler-util/src/bitcoin.ts
@@ -23,7 +23,7 @@
  * Imports.
  */
 import { AmountJson, Amounts } from "./amounts.js";
-import { getRandomBytes, decodeCrock } from "./talerCrypto.js";
+import { decodeCrock } from "./talerCrypto.js";
 import * as segwit from "./segwit_addr.js";
 
 export interface SegwitAddrs {
@@ -44,13 +44,14 @@ const hext2buf = (hexString: string) =>
 
 export function generateFakeSegwitAddress(
   reservePub: string,
-  addr: string,
+  addr: string
 ): SegwitAddrs {
   const pub = decodeCrock(reservePub);
 
-  const first_rnd = getRandomBytes(4);
-  const second_rnd = new Uint8Array(first_rnd.length);
-  second_rnd.set(first_rnd);
+  const first_rnd = new Uint8Array(4);
+  first_rnd.set(pub.subarray(0, 4))
+  const second_rnd = new Uint8Array(4);
+  second_rnd.set(pub.subarray(0, 4));
 
   first_rnd[0] = first_rnd[0] & 0b0111_1111;
   second_rnd[0] = second_rnd[0] | 0b1000_0000;
@@ -58,6 +59,7 @@ export function generateFakeSegwitAddress(
   const first_part = new Uint8Array(first_rnd.length + pub.length / 2);
   first_part.set(first_rnd, 0);
   first_part.set(pub.subarray(0, 16), 4);
+
   const second_part = new Uint8Array(first_rnd.length + pub.length / 2);
   second_part.set(second_rnd, 0);
   second_part.set(pub.subarray(16), 4);
diff --git a/packages/taler-util/src/payto.ts b/packages/taler-util/src/payto.ts
index dd764e42d..7dcb28098 100644
--- a/packages/taler-util/src/payto.ts
+++ b/packages/taler-util/src/payto.ts
@@ -49,9 +49,8 @@ export interface PaytoUriTalerBank extends PaytoUriGeneric {
 export interface PaytoUriBitcoin extends PaytoUriGeneric {
   isKnown: true;
   targetType: "bitcoin";
-  generateSegwitAddress: (r: string) => { addr1: string; addr2: string };
-  addr1?: string;
-  addr2?: string;
+  addr1: string;
+  addr2: string;
 }
 
 const paytoPfx = "payto://";
@@ -131,7 +130,7 @@ export function parsePaytoUri(s: string): PaytoUri | undefined {
   const searchParams = new URLSearchParams(search || "");
 
   searchParams.forEach((v, k) => {
-    params[v] = k;
+    params[k] = v;
   });
 
   if (targetType === "x-taler-bank") {
@@ -157,15 +156,18 @@ export function parsePaytoUri(s: string): PaytoUri | undefined {
     };
   }
   if (targetType === "bitcoin") {
+    const msg = /\b([A-Z0-9]{52})\b/.exec(params["message"])
+    const reserve = !msg ? params["subject"] : msg[0];
+    const { addr1, addr2 } = generateFakeSegwitAddress(reserve, targetPath);
+
     const result: PaytoUriBitcoin = {
       isKnown: true,
       targetPath,
       targetType,
       params,
-      generateSegwitAddress: (): any => null,
+      addr1, addr2
     };
 
-    result.generateSegwitAddress = buildSegwitGenerator(result, targetPath);
     return result;
   }
   return {
diff --git a/packages/taler-wallet-webextension/src/components/BankDetailsByPaytoType.tsx b/packages/taler-wallet-webextension/src/components/BankDetailsByPaytoType.tsx
index ac6f8541e..b20fc2d59 100644
--- a/packages/taler-wallet-webextension/src/components/BankDetailsByPaytoType.tsx
+++ b/packages/taler-wallet-webextension/src/components/BankDetailsByPaytoType.tsx
@@ -45,10 +45,6 @@ export function BankDetailsByPaytoType({
 
   if (payto.isKnown && payto.targetType === "bitcoin") {
     const min = segwitMinAmount(amount.currency);
-    if (typeof window !== "undefined") {
-      //FIXME: generate (and possibly save in db?) in wallet-core
-      payto.generateSegwitAddress(subject);
-    }
     return (
       <section style={{ textAlign: "left" }}>
         <p>
diff --git a/packages/taler-wallet-webextension/src/wallet/ManualWithdrawPage.tsx b/packages/taler-wallet-webextension/src/wallet/ManualWithdrawPage.tsx
index a8c6b3c1a..8b8d375de 100644
--- a/packages/taler-wallet-webextension/src/wallet/ManualWithdrawPage.tsx
+++ b/packages/taler-wallet-webextension/src/wallet/ManualWithdrawPage.tsx
@@ -66,9 +66,6 @@ export function ManualWithdrawPage({ currency, onCancel }: Props): VNode {
       );
       const payto = response.exchangePaytoUris[0];
       const paytoURI = parsePaytoUri(payto);
-      if (paytoURI && paytoURI.isKnown && paytoURI.targetType === "bitcoin") {
-        paytoURI.generateSegwitAddress(response.reservePub);
-      }
       setSuccess({ exchangeBaseUrl, response, amount, paytoURI, payto });
     } catch (e) {
       if (e instanceof Error) {