From 6ccbfb692906ed803a407c20da4d1b4fa6e78a85 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 7 Apr 2025 06:14:16 +0530
Subject: [PATCH] Ensure cleanup waits on workers

---
 src/calibre/gui2/viewer/convert_book.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/calibre/gui2/viewer/convert_book.py b/src/calibre/gui2/viewer/convert_book.py
index e581779421..ea07ec13c2 100644
--- a/src/calibre/gui2/viewer/convert_book.py
+++ b/src/calibre/gui2/viewer/convert_book.py
@@ -176,10 +176,12 @@ def clean_running_workers():
     global preloaded_worker
     if preloaded_worker is not None:
         preloaded_worker.kill()
+        preloaded_worker.wait()
         preloaded_worker = None
     for p in running_workers:
         if p.poll() is None:
             p.kill()
+            p.wait()
     del running_workers[:]