Comment 2 for bug 1888609

Yes in the viewer.

calibre Debug log
calibre 4.21 [64bit] embedded-python: True is64bit: True
Windows-10-10.0.18362 Windows ('64bit', 'WindowsPE')
('Windows', '10', '10.0.18362')
Python 2.7.16+
Windows: ('10', '10.0.18362', '', u'Multiprocessor Free')
Interface language: None
Successfully initialized third party plugins: DeDRM (6, 6, 1) && EpubMerge (2, 9, 0)
calibre 4.21 [64bit] embedded-python: True is64bit: True
Windows-10-10.0.18362 Windows ('64bit', 'WindowsPE')
('Windows', '10', '10.0.18362')
Python 2.7.16+
Windows: ('10', '10.0.18362', '', u'Multiprocessor Free')
Interface language: None
Successfully initialized third party plugins: DeDRM (6, 6, 1) && EpubMerge (2, 9, 0)
Turning on automatic hidpi scaling
devicePixelRatio: 1.0
logicalDpi: 96.0 x 96.0
physicalDpi: 101.6 x 101.6
Using calibre Qt style: True
[0.00] Starting up...
[0.00] Showing splash screen...
[0.72] splash screen shown
[0.72] Initializing db...
[0.75] db initialized
[0.75] Constructing main UI...
EpubMerge: DEBUG: 2020-07-24 07:36:39,780: calibre_plugins.epubmerge.epubmerge_plugin(157): macmenuhack file_path:C:\Users\gary\AppData\Roaming\calibre\plugins\fanficfare_macmenuhack.txt
[3.42] main UI initialized...
[3.42] Hiding splash screen
[21.24] splash screen hidden
[21.24] Started up in 21.24 seconds with 215 books