diff --git a/electrum_grs/gui/qml/qetxdetails.py b/electrum_grs/gui/qml/qetxdetails.py
index 6df334ecbc68..2e65df6ca916 100644
--- a/electrum_grs/gui/qml/qetxdetails.py
+++ b/electrum_grs/gui/qml/qetxdetails.py
@@ -260,7 +260,7 @@ def update(self, from_txid: bool = False):
 
         if from_txid:
             self._tx = self._wallet.wallet.db.get_transaction(self._txid)
-            assert self._tx is not None
+            assert self._tx is not None, f'unknown txid "{self._txid}"'
 
         #self._logger.debug(repr(self._tx.to_json()))
 
diff --git a/electrum_grs/lnworker.py b/electrum_grs/lnworker.py
index 3df063964a5b..d64606fe30da 100644
--- a/electrum_grs/lnworker.py
+++ b/electrum_grs/lnworker.py
@@ -278,7 +278,6 @@ async def cb(reader, writer):
             except OSError as e:
                 self.logger.error(f"cannot listen for lightning p2p. error: {e!r}")
 
-    @ignore_exceptions  # don't kill outer taskgroup
     async def main_loop(self):
         self.logger.info("starting taskgroup.")
         try:
@@ -937,6 +936,8 @@ async def stop(self):
         if self.lnwatcher:
             await self.lnwatcher.stop()
             self.lnwatcher = None
+        if self.swap_manager:  # may not be present in tests
+            await self.swap_manager.stop()
 
     async def wait_for_received_pending_htlcs_to_get_removed(self):
         assert self.stopping_soon is True
diff --git a/electrum_grs/plugins/swapserver/qt.py b/electrum_grs/plugins/swapserver/qt.py
deleted file mode 100644
index 7add7a3861c7..000000000000
--- a/electrum_grs/plugins/swapserver/qt.py
+++ /dev/null
@@ -1,31 +0,0 @@
-#!/usr/bin/env python
-#
-# Electrum - Lightweight Bitcoin Client
-# Copyright (C) 2023 The Electrum Developers
-#
-# Permission is hereby granted, free of charge, to any person
-# obtaining a copy of this software and associated documentation files
-# (the "Software"), to deal in the Software without restriction,
-# including without limitation the rights to use, copy, modify, merge,
-# publish, distribute, sublicense, and/or sell copies of the Software,
-# and to permit persons to whom the Software is furnished to do so,
-# subject to the following conditions:
-#
-# The above copyright notice and this permission notice shall be
-# included in all copies or substantial portions of the Software.
-#
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
-# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
-# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-# SOFTWARE.
-
-
-from .swapserver import SwapServerPlugin
-
-class Plugin(SwapServerPlugin):
-    pass
-
diff --git a/electrum_grs/plugins/trustedcoin/trustedcoin.py b/electrum_grs/plugins/trustedcoin/trustedcoin.py
index 03d113695791..7dba0279b611 100644
--- a/electrum_grs/plugins/trustedcoin/trustedcoin.py
+++ b/electrum_grs/plugins/trustedcoin/trustedcoin.py
@@ -393,8 +393,6 @@ def add_new_billing_address(self, billing_index: int, address: str, addr_type: s
         self._billing_addresses[addr_type] = billing_addresses_of_this_type
         self.db.put('trustedcoin_billing_addresses', self._billing_addresses['legacy'])
         self.db.put('trustedcoin_billing_addresses_segwit', self._billing_addresses['segwit'])
-        # FIXME this often runs in a daemon thread, where storage.write will fail
-        self.db.write()
 
     def is_billing_address(self, addr: str) -> bool:
         return addr in self._billing_addresses_set
diff --git a/electrum_grs/submarine_swaps.py b/electrum_grs/submarine_swaps.py
index 801880933be5..0abca4db3303 100644
--- a/electrum_grs/submarine_swaps.py
+++ b/electrum_grs/submarine_swaps.py
@@ -207,8 +207,20 @@ def start_network(self, *, network: 'Network', lnwatcher: 'LNWalletWatcher'):
             self.add_lnwatcher_callback(swap)
 
         self.taskgroup = OldTaskGroup()
-        coro = self.pay_pending_invoices()
-        asyncio.run_coroutine_threadsafe(self.taskgroup.spawn(coro), self.network.asyncio_loop)
+        asyncio.run_coroutine_threadsafe(self.main_loop(), self.network.asyncio_loop)
+
+    async def main_loop(self):
+        self.logger.info("starting taskgroup.")
+        try:
+            async with self.taskgroup as group:
+                await group.spawn(self.pay_pending_invoices())
+        except Exception as e:
+            self.logger.exception("taskgroup died.")
+        finally:
+            self.logger.info("taskgroup stopped.")
+
+    async def stop(self):
+        await self.taskgroup.cancel_remaining()
 
     async def pay_invoice(self, key):
         self.logger.info(f'trying to pay invoice {key}')
diff --git a/electrum_grs/tests/test_lnpeer.py b/electrum_grs/tests/test_lnpeer.py
index e39ee9af7317..70278dfb39b3 100644
--- a/electrum_grs/tests/test_lnpeer.py
+++ b/electrum_grs/tests/test_lnpeer.py
@@ -147,6 +147,7 @@ def __init__(self, *, local_keypair: Keypair, chans: Iterable['Channel'], tx_que
         self.network = MockNetwork(tx_queue, config=self.config)
         self.taskgroup = OldTaskGroup()
         self.lnwatcher = None
+        self.swap_manager = None
         self.listen_server = None
         self._channels = {chan.channel_id: chan for chan in chans}
         self.payment_info = {}
diff --git a/electrum_grs/wallet.py b/electrum_grs/wallet.py
index 13bbcc57e2d4..e4b9c0c9749a 100644
--- a/electrum_grs/wallet.py
+++ b/electrum_grs/wallet.py
@@ -452,7 +452,6 @@ def __init__(self, db: WalletDB, *, config: SimpleConfig):
     def _init_lnworker(self):
         self.lnworker = None
 
-    @ignore_exceptions  # don't kill outer taskgroup
     async def main_loop(self):
         self.logger.info("starting taskgroup.")
         try: