[rosalita]

Ah, thank you both! I didn't even notice the "updated plugin available" notice at the bottom of the window — poor form on my part. Regretfully, however, updating the plugin (current version shows as 3.5.3) and restarting Calibre has not solved the problem.

The error dialog:

calibre, version 5.26.0
ERROR: Error: Error communicating with device

Failed to process Frederica by Georgette Heyer: list index out of range

Traceback (most recent call last):
File "calibre_plugins.kobotouch_extended.device.driver" , line 270, in _modify_epub
common.modify_epub(
File "calibre_plugins.kobotouch_extended.common", line 236, in modify_epub
container.convert()
File "calibre_plugins.kobotouch_extended.container" , line 379, in convert
self.__run_async_over_content(self.add_kobo_spans)
File "calibre_plugins.kobotouch_extended.container" , line 375, in __run_async_over_content
self.__run_async(func, names)
File "calibre_plugins.kobotouch_extended.container" , line 368, in __run_async
future.result(timeout=10)
File "concurrent/futures/_base.py", line 432, in result
File "concurrent/futures/_base.py", line 388, in __get_result
File "concurrent/futures/thread.py", line 57, in run
File "calibre_plugins.kobotouch_extended.container" , line 501, in add_kobo_spans
body = root.xpath("./xhtml:body", namespaces={"xhtml": XHTML_NAMESPACE})[0]
IndexError: list index out of range

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "calibre/gui2/device.py", line 89, in run
File "calibre/gui2/device.py", line 595, in _upload_books
File "calibre_plugins.kobotouch_extended.device.driver" , line 400, in upload_books
return super(KOBOTOUCHEXTENDED, self).upload_books(
File "calibre/devices/kobo/driver.py", line 2137, in upload_books
File "calibre_plugins.kobotouch_extended.device.driver" , line 296, in _modify_epub
raise e.__class__(msg).with_traceback(tb)
File "calibre_plugins.kobotouch_extended.device.driver" , line 270, in _modify_epub
common.modify_epub(
File "calibre_plugins.kobotouch_extended.common", line 236, in modify_epub
container.convert()
File "calibre_plugins.kobotouch_extended.container" , line 379, in convert
self.__run_async_over_content(self.add_kobo_spans)
File "calibre_plugins.kobotouch_extended.container" , line 375, in __run_async_over_content
self.__run_async(func, names)
File "calibre_plugins.kobotouch_extended.container" , line 368, in __run_async
future.result(timeout=10)
File "concurrent/futures/_base.py", line 432, in result
File "concurrent/futures/_base.py", line 388, in __get_result
File "concurrent/futures/thread.py", line 57, in run
File "calibre_plugins.kobotouch_extended.container" , line 501, in add_kobo_spans
body = root.xpath("./xhtml:body", namespaces={"xhtml": XHTML_NAMESPACE})[0]
IndexError: Failed to process Frederica by Georgette Heyer: list index out of range