diff --git a/plugin.py b/plugin.py
index 410b767..60c34dc 100644
--- a/plugin.py
+++ b/plugin.py
@@ -38,8 +38,6 @@ async def disconnect_client():
     for vws in CLIENT.workspaces.values():
         vws.cleanup()
 
-    CLIENT = None
-
 
 def plugin_unloaded():
     global CLIENT
@@ -51,10 +49,26 @@ def plugin_unloaded():
 # Listeners
 ##############################################################################
 class EventListener(sublime_plugin.EventListener):
-    def on_exit(self) -> None:
+    def on_exit(self):
         global CLIENT
         CLIENT.tm.release(True)
 
+    def on_pre_close_window(self, window):
+        global CLIENT
+        s = window.settings()
+        if s.get(g.CODEMP_WINDOW_TAG, False):
+            for wsid in s[g.CODEMP_WINDOW_WORKSPACES]:
+                ws = CLIENT[wsid]
+                if ws is not None:
+                    status_log(
+                        f"current active: {CLIENT.active_workspace.id}, ws = {ws.id}"
+                    )
+                    if ws.id == CLIENT.active_workspace.id:
+                        CLIENT.active_workspace = None
+                        CLIENT.tm.stop(f"{g.CURCTL_TASK_PREFIX}-{ws.id}")
+                    ws.cleanup()
+                    del CLIENT.workspaces[wsid]
+
 
 class CodempClientViewEventListener(sublime_plugin.ViewEventListener):
     @classmethod
@@ -102,7 +116,7 @@ class CodempClientViewEventListener(sublime_plugin.ViewEventListener):
         vbuff = CLIENT[wsid].get_by_local(self.view.buffer_id())
         vbuff.cleanup()
 
-        CLIENT.tm.stop_and_pop(f"{g.BUFFCTL_TASK_PREFIX}-{vbuff.codemp_id}")
+        CLIENT.tm.stop(f"{g.BUFFCTL_TASK_PREFIX}-{vbuff.codemp_id}")
 
 
 class CodempClientTextChangeListener(sublime_plugin.TextChangeListener):
@@ -283,6 +297,7 @@ class RawBufferId(sublime_plugin.TextInputHandler):
     def placeholder(self):
         return "Buffer Id"
 
+
 # Share Command
 # #############################################################################
 # class CodempShareCommand(sublime_plugin.WindowCommand):
diff --git a/src/TaskManager.py b/src/TaskManager.py
index 43588a1..f5b4714 100644
--- a/src/TaskManager.py
+++ b/src/TaskManager.py
@@ -1,4 +1,5 @@
 from typing import Optional
+import asyncio
 import Codemp.ext.sublime_asyncio as rt
 
 
@@ -16,17 +17,18 @@ class TaskManager:
     def sync(self, coro):
         rt.sync(coro)
 
-    def store(self, task):
-        self.tasks.append(task)
+    def remove_stopped(self):
+        self.tasks = list(filter(lambda T: not T.cancelled(), self.tasks))
 
-    def store_named(self, task, name=None):
-        task.set_name(name)
-        self.store(task)
+    def store(self, task, name=None):
+        if name is not None:
+            task.set_name(name)
+        self.tasks.append(task)
+        self.remove_stopped()
 
     def store_named_lambda(self, name):
         def _store(task):
-            task.set_name(name)
-            self.store(task)
+            self.store(task, name)
 
         return _store
 
@@ -44,20 +46,20 @@ class TaskManager:
             return self.task.pop(idx)
         return None
 
+    async def _stop(self, task):
+        task.cancel()  # cancelling a task, merely requests a cancellation.
+        try:
+            await task
+        except asyncio.CancelledError:
+            return
+
     def stop(self, name):
         t = self.get_task(name)
         if t is not None:
-            t.cancel()
-
-    def stop_and_pop(self, name) -> Optional:
-        idx, task = next(
-            ((i, t) for (i, t) in enumerate(self.tasks) if t.get_name() == name),
-            (None, None),
-        )
-        if idx is not None:
-            task.cancel()
-            return self.tasks.pop(idx)
+            rt.sync(
+                self._stop(t)
+            )  # awaiting the task blocks until it actually is finished.
 
     def stop_all(self):
         for task in self.tasks:
-            task.cancel()
+            rt.sync(self._stop(task))
diff --git a/src/codemp_client.py b/src/codemp_client.py
index a2bcf30..d6c71f9 100644
--- a/src/codemp_client.py
+++ b/src/codemp_client.py
@@ -73,7 +73,7 @@ class VirtualWorkspace:
 
         # mapping remote ids -> local ids
         self.id_map: dict[str, str] = {}
-        self.active_buffers: dict[str, VirtualBuffer] = {}
+        self.active_buffers: dict[str, VirtualBuffer] = {}  # local_id -> VBuff
 
         # initialise the virtual filesystem
         tmpdir = tempfile.mkdtemp(prefix="codemp_")
@@ -90,6 +90,13 @@ class VirtualWorkspace:
         )
         self.sublime_window.set_project_data(proj_data)
 
+        s: dict = self.sublime_window.settings()
+        if s.get(g.CODEMP_WINDOW_TAG, False):
+            s[g.CODEMP_WINDOW_WORKSPACES].append(self.id)
+        else:
+            s[g.CODEMP_WINDOW_TAG] = True
+            s[g.CODEMP_WINDOW_WORKSPACES] = [self.id]
+
     def add_buffer(self, remote_id: str, vbuff: VirtualBuffer):
         self.id_map[remote_id] = vbuff.view.buffer_id()
         self.active_buffers[vbuff.view.buffer_id()] = vbuff
@@ -100,6 +107,8 @@ class VirtualWorkspace:
         for vbuff in self.active_buffers.values():
             vbuff.view.close()
 
+        self.active_buffers = {}  # drop all buffers, let them be garbace collected (hopefully)
+
         d = self.sublime_window.project_data()
         newf = list(
             filter(
@@ -112,6 +121,10 @@ class VirtualWorkspace:
         status_log(f"cleaning up virtual workspace '{self.id}'")
         shutil.rmtree(self.rootdir, ignore_errors=True)
 
+        s = self.sublime_window.settings()
+        del s[g.CODEMP_WINDOW_TAG]
+        del s[g.CODEMP_WINDOW_WORKSPACES]
+
     def get_by_local(self, local_id: str) -> Optional[VirtualBuffer]:
         return self.active_buffers.get(local_id)
 
@@ -171,7 +184,9 @@ class VirtualClient:
         try:
             await self.handle.connect(server_host)
         except Exception as e:
-            sublime.error_message(f"Could not connect:\n Make sure the server is up.\nerror: {e}")
+            sublime.error_message(
+                f"Could not connect:\n Make sure the server is up.\nerror: {e}"
+            )
             return
 
         id = await self.handle.user_id()
@@ -185,7 +200,9 @@ class VirtualClient:
             await self.handle.login(user, password, workspace_id)
         except Exception as e:
             status_log(f"Failed to login to workspace '{workspace_id}'.\nerror: {e}")
-            sublime.error_message(f"Failed to login to workspace '{workspace_id}'.\nerror: {e}")
+            sublime.error_message(
+                f"Failed to login to workspace '{workspace_id}'.\nerror: {e}"
+            )
             return
 
         try:
@@ -193,7 +210,9 @@ class VirtualClient:
             workspace_handle = await self.handle.join_workspace(workspace_id)
         except Exception as e:
             status_log(f"Could not join workspace '{workspace_id}'.\nerror: {e}")
-            sublime.error_message(f"Could not join workspace '{workspace_id}'.\nerror: {e}")
+            sublime.error_message(
+                f"Could not join workspace '{workspace_id}'.\nerror: {e}"
+            )
             return
 
         vws = VirtualWorkspace(self, workspace_id, workspace_handle)
@@ -233,7 +252,10 @@ class VirtualClient:
 
             except asyncio.CancelledError:
                 status_log(f"cursor worker for '{vws.id}' stopped...")
-                return
+                raise
+            except Exception as e:
+                status_log(f"cursor worker '{vws.id}' crashed:\n{e}")
+                raise
 
         self.tm.dispatch(
             move_cursor_task(virtual_workspace),
@@ -280,7 +302,11 @@ class VirtualClient:
                     )
 
             except asyncio.CancelledError:
-                status_log("'{}' buffer worker stopped...".format(vb.codemp_id))
+                status_log(f"'{vb.codemp_id}' buffer worker stopped...")
+                raise
+            except Exception as e:
+                status_log(f"buffer worker '{vb.codemp_id}' crashed:\n{e}")
+                raise
 
         self.tm.dispatch(
             apply_buffer_change_task(vbuff),
diff --git a/src/globals.py b/src/globals.py
index dd9fb74..55fd01d 100644
--- a/src/globals.py
+++ b/src/globals.py
@@ -1,9 +1,13 @@
 BUFFCTL_TASK_PREFIX = "buffer-ctl"
 CURCTL_TASK_PREFIX = "cursor-ctl"
+
 CODEMP_BUFFER_TAG = "codemp-buffer"
 CODEMP_REMOTE_ID = "codemp-buffer-id"
 CODEMP_WORKSPACE_ID = "codemp-workspace-id"
 
+CODEMP_WINDOW_TAG = "codemp-window"
+CODEMP_WINDOW_WORKSPACES = "codemp-workspaces"
+
 WORKSPACE_FOLDER_PREFIX = "CODEMP::"
 SUBLIME_REGIONS_PREFIX = "codemp-cursors"
 SUBLIME_STATUS_ID = "z_codemp_buffer"
diff --git a/src/lib.rs b/src/lib.rs
index 88c554c..886bbe6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,6 +1,6 @@
 use codemp::proto::common::Identity;
 use pyo3::types::PyList;
-use std::{format, ops::Deref, sync::Arc};
+use std::{format, sync::Arc};
 use tokio::sync::RwLock;
 
 use codemp::prelude::*;