https://bugs.kde.org/show_bug.cgi?id=509015

--- Comment #5 from Ben <[email protected]> ---
Comment on attachment 184638
  --> https://bugs.kde.org/attachment.cgi?id=184638
Tests & Conclusions & Ruled out Possibilities

File Managers - Krusader - Does not always display Thumbnails on every folder
that has videos in them - TESTS AND CONCLUSIONS:




Krusader - Intermittant Displaying Previews of 'Folder' Thumbnails on NTFS
Drives/Partitions

https://bugs.kde.org/show_bug.cgi?id=509015

DATE BUG SUBMITTED: Tuesday the 2nd of September, 2025
TIME REPORTED: 11.49 AM NZDT




WHY:
----

A folder has to have a minimal number/amount of video files in in before the
default thumbnailer will create any thumbnails
for the folder

This can only be checked using Dolphin File Manager
Look at the number of items displayex underneath the 'Size' field in Dolphin
You can order all files by item size in Dolphin File Manager by the 'Size'
field

While File Krusader does have its own 'Size' field, it's field does NOT display
any item numbers

NOTE: It does not matter if the folder /usr/share/thumbnailers/ has no files
(no thumnbnailers in it) either




FOLDERS WITH INCLUDED FILES - NUMBER OF ITEMS LISTED:
-----------------------------------------------------

/home/USB HDD - 4TB No 2 - (USB 2) - My Book/
Links point to this USB HDD

Dolphin File Manager:

Number of Items    Location:




TEST 1 - COPY FILES FROM SHORTCUT LINK DIRECTLY BACK TO SAME USB DRIVE:
-----------------------------------------------------------------------


 - COPY FOLDERS FROM LINK TO /home/USB HDD - 4TB No 2 - (USB 2) - My Book/
   -----------------------------------------------------------------------

26                 /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 1
5                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 2A
24                 /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 1
6                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 2

RESULT: Same issue




 - COPY FOLDERS FROM /home/USB HDD - 4TB No 2 - (USB 2) - My Book/ - TO
/home/dragonforce/Videos - DragonForce/ - EXT4 FORMATTED SSD
   -----------------------------------------------------------------

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: NO  - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: NO  - ALF 2
THUMBNAILS: NO  - ALF 3

TO /home/dragonforce/Videos - DragonForce/



RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: YES - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: YES  - ALF 2
THUMBNAILS: YES  - ALF 3




TEST 2 - COPY FOLDERS FROM USB DRIVE DIRECTLY TO /home/USB HDD - 3TB No 1 - My
Book/ (NTFS):
--------------------------------------------------------------------------------------------

COPY FROM /home/USB HDD - 4TB No 2 - (USB 2) - My Book/ (NTFS) - FOLDERS

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: NO  - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: NO  - ALF 2
THUMBNAILS: NO  - ALF 3

TO: /home/USB HDD - 3TB No 1 - My Book/ (NTFS)

RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: NO  - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: NO  - ALF 2
THUMBNAILS: NO  - ALF 3




TEST 3 - COPY FOLDERS FROM USB HDD TO /home/USB HDD - 3TB No 2 - My Book
(EXT4)/ - EXT4 FORMATTED:
--------------------------------------------------------------------------------------------------

COPY FROM /home/USB HDD - 4TB No 2 - (USB 2) - My Book/ - FOLDERS

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: NO  - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: NO  - ALF 2
THUMBNAILS: NO  - ALF 3

TO: /home/USB HDD - 3TB No 2 - My Book (EXT4)/

RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: YES - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: YES - ALF 2
THUMBNAILS: YES - ALF 3




TEST 4 - COPY OF ALL 4 FOLDERS TO USB 2.0 LEXAR FLASH DRIVE - FORMATTED AS FAT
32:
----------------------------------------------------------------------------------

Flash Drive Mounted by KDE GUI USB Mounter 'Disks & Devices'
Mount Point of Flash Drive: /run/media/dragonforce/Lexar/
Flash Drive connected to USB 3.0 USB Port on front of PC

Number of Items:    Location:

26                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 1
5                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 2A
24                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 1
6                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 2

Close Krusader
TERMINAL: rm -rf ~/.cache/thumbnails/*
Open Krusader


RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: YES - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: YES - ALF 2
THUMBNAILS: YES - ALF 3




TEST 5 - COPY OF ALL 4 FOLDERS TO USB 2.0 LEXAR FLASH DRIVE - FORMATTED AS NTFS
- FORMATTED BY GPARTED:
-------------------------------------------------------------------------------------------------------

Flash Drive Mounted by KDE GUI USB Mounter 'Disks & Devices'
Mount Point of Flash Drive: /run/media/dragonforce/1C617A0B681AB3A0/
Flash Drive connected to USB 3.0 USB Port on front of PC

Number of Items:    Location:

26                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 1
5                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 2A
24                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 1
6                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 2

RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: YES - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: YES - ALF 2
THUMBNAILS: YES - ALF 3




TEST 6 - COPY OF ALL 4 FOLDERS TO /home/USB HDD - 4TB No 8 - My Passport -
FORMATTED AS NTFS:
---------------------------------------------------------------------------------------------

Number of Items:    Location:

26                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 1
5                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 2A
24                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 1
6                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 2

RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: YES - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: YES - ALF 2
THUMBNAILS: YES - ALF 3

Close Krusader
TERMINAL: rm -rf ~/.cache/thumbnails/*
Open Krusader


RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: YES - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: YES - ALF 2
THUMBNAILS: YES - ALF 3




TEST 7 - COPY FOLDERS FROM ORIGINAL USB HDD TO /home/USB HDD - 3TB No 1 - My
Book/EMPTY-FOLDER - INTO AN EMPTY FOLDER - NTFS FORMATTED:
---------------------------------------------------------------------------------------------------------------------------------------

NOTE: This test is almost identical to test number 2 with the exception in that
instead of copying the 4 folders to the ROOT of thr drive
      we are instead going to copy the 4 folders into an empty folder, and
review that folder


      Number of Items:    Location:

26                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 1
5                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/Alf - Season 2A
24                  /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 1
6                   /home/dragonforce/1 - Library/Media - Videos - Non-Standard
- FLV - AVI - MPG - The BIG Archive/ALF 2

COPY TO: /home/USB HDD - 3TB No 1 - My Book/EMPTY-FOLDER

RESULT:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: YES - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: YES - ALF 2
THUMBNAILS: YES - ALF 3


Close Krusader
TERMINAL: rm -rf ~/.cache/thumbnails/*
Open Krusader

While the previews are loading up for everything in the ROOT of the drive,
immediately goto into the folder called EMPTY-FOLDER

RESULTS:

THUMBNAILS: YES - Alf - Season 1
THUMBNAILS: NO  - Alf - Season 2A
THUMBNAILS: YES - ALF 1
THUMBNAILS: NO  - ALF 2

CONCLUSION: This PROVES That there is an intermittant issue going on with with
the creation of thumbnails for the Folders that contain video files no NTFS
Drives/Partitions




-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

CONCLUSION:
-----------

CONCLUSION: Test 7 - This PROVES That there is an intermittant issue going on
with with the creation of thumbnails for the Folders that contain video files
no NTFS Drives/Partitions

NTFS Drives/Partitions for some reason often prevent 'Folder Thumbnails' from
being generated
     - It has been observed in my case, that if the folder contains LESS than
17 video files in it, then no folder thumbnails get created
     - Also that if i run a script to add multiple copyies of a video file to
the folder, this too often makes no differance even if i have over 17 files
EXT4 Drives/Partitions Do not have this limitation



NTFS DRIVE/PARTITION MOUNT CONSIDERATIONS:
------------------------------------------

Tests will have to be performed on NTFS Drive/Partitions mount options specific
to NTFS using the ntfs-3g driver
Also to be reviewed: u-disks2 NTFS Drive/Partition "Exclusion" Lists -
/etc/udev/rules.d/99-udisks2-ignore.rules




VARIABLES TESTED AND CONCLUDED AS NOT RELEVANT:
-----------------------------------------------


ACL's - Makes no differance

Read-Only vs. Read-Write:If an NTFS partition is mounted read-only (e.g., due
to a dirty volume or fast startup issues), thumbnailers may fail to write
thumbnail cache files, preventing folder thumbnails.

Test Implication: The test results don’t explicitly mention read-only mounts,
but this could be a factor if the NTFS drives were not properly unmounted from
Windows (e.g., fast startup enabled).

Hypothesis: A read-only mount could prevent thumbnail creation for folders with
fewer files if the thumbnailer requires write access to cache thumbnails.

uid, gid, umask:These options control user and group permissions for mounted
NTFS partitions. If set incorrectly (e.g., uid=root, umask=0222), the
thumbnailer process (running as a non-root user) may lack read access to files.

Hypothesis: Restrictive permissions set via ntfs-3g mount options could limit
thumbnailer access to video files, especially in folders with fewer files,
causing thumbnail generation to fail unless a sufficient number of accessible
files are present.

Optional NTFS mount options such as big_write - Makes no differance



------------------------------------------------------------------------------------

Confirmed as making no differance

/etc/udev/rules.d/

99-udisks2-ignore.rules

# Ignore specific USB drives from udisks2 automounting
ENV{ID_FS_UUID}=="409C1078450547A4", ENV{UDISKS_AUTO}="0",
ENV{UDISKS_IGNORE}="1"
ENV{ID_FS_UUID}=="7858607050FA5558", ENV{UDISKS_AUTO}="0",
ENV{UDISKS_IGNORE}="1"
ENV{ID_FS_UUID}=="483ACC0A3ACBF2CC", ENV{UDISKS_AUTO}="0",
ENV{UDISKS_IGNORE}="1"
ENV{ID_FS_UUID}=="655B2467153C6767", ENV{UDISKS_AUTO}="0",
ENV{UDISKS_IGNORE}="1"
ENV{ID_FS_UUID}=="67485E91550DB9F7", ENV{UDISKS_AUTO}="0",
ENV{UDISKS_IGNORE}="1"
ENV{ID_FS_UUID}=="3B575B303D8AA041", ENV{UDISKS_AUTO}="0",
ENV{UDISKS_IGNORE}="1"
ENV{ID_FS_UUID}=="474E79A9081CE0F4", ENV{UDISKS_AUTO}="0",
ENV{UDISKS_IGNORE}="1"

------------------------------------------------------------------------------------

 - FSTAB FILE WITH EXTRA NTFS MOUNT OPTIONS:


UUID=847c1296-1ff4-41b8-a0fb-a2be8d71857e  /          ext4  defaults      0  1
UUID=83B1-C34B                             /boot/efi  vfat  utf8          0  2
UUID=4c060c41-2a91-4b68-b01e-0102a78f1284  /home      ext4  data=ordered  0  2


# 320 GB USB HDD - NTFS Maxtor
UUID=409C1078450547A4                     
/home/USB\040HDD\040-\040320GB\040-\040Maxtor    ntfs-3g   defaults,nofail     
                0  0

# 320 GB USB HDD - NTFS - My Passport
UUID=7858607050FA5558                     
/home/USB\040HDD\040-\040320GB\040-\040My\040Passport  ntfs-3g  
defaults,nofail                      0  0

# 3TB No 1 USB HDD - NTFS - My Book
UUID=655B2467153C6767                     
/home/USB\040HDD\040-\0403TB\040No\0401\040-\040My\040Book  ntfs-3g
users,uid=1000,gid=1000,umask=000,permissions,big_writes,exec,defaults,noauto,nofail,x-systemd.automount,x-systemd.device-timeout=5
0 2

# 4TB No 1 USB HDD - NTFS - My Book
UUID=67485E91550DB9F7                     
/home/USB\040HDD\040-\0404TB\040No\0401\040-\040My\040Book  ntfs-3g
users,uid=1000,gid=1000,umask=022,big_writes,exec,defaults,noauto,nofail,x-systemd.automount,x-systemd.device-timeout=5
0 2

# 4TB No 2  USB HDD - NTFS - My Book
UUID=3B575B303D8AA041                     
/home/USB\040HDD\040-\0404TB\040No\0402\040-\040(USB\0402)\040-\040My\040Book 
ntfs-3g
users,uid=1000,gid=1000,umask=022,big_writes,exec,defaults,noauto,nofail,x-systemd.automount,x-systemd.device-timeout=5
0 2

# 4TB No 3 - USB HDD - NTFS - My Book
UUID=474E79A9081CE0F4                     
/home/USB\040HDD\040-\0404TB\040No\0403\040-\040My\040Book  ntfs-3g
users,uid=1000,gid=1000,umask=022,big_writes,exec,defaults,noauto,nofail,x-systemd.automount,x-systemd.device-timeout=5
0 2

# 3TB No 2 USB HDD - EXT4 - My Book
UUID=7ced6bd9-db96-4e0f-81f2-ce0ae8d41127 
/home/USB\040HDD\040-\0403TB\040No\0402\040-\040My\040Book\040(EXT4)  ext4  
data=ordered,nofail                  0  0

# 4TB No 4 - USB HDD - EXT4
UUID=9247bf5f-fecb-4ef7-baee-79479be51d27 
/home/USB\040HDD\040-\0404TB\040No\0404\040-\040Elements\040(EXT4)   ext4     
data=ordered,nofail 0  0

# 4TB No 5 USB HDD - EXT4 - My Passport
UUID=10f099e7-0f37-4a88-bac4-9526e142af76 
/home/USB\040HDD\040-\0404TB\040No\0405\040-\040My\040Passport\040(EXT4)  ext4 
 data=ordered,nofail                  0  0

# 4TB No 6 USB HDD - EXT4 - My Passport
UUID=e52a9b33-4d3f-4231-8760-e35688814281 
/home/USB\040HDD\040-\0404TB\040No\0406\040-\040My\040Passport\040(EXT4) ext4  
data=ordered,nofail 0  0

# 4TB No 7 - Elements SE - EXT4
UUID=ff240d57-6269-4d86-8f8a-48d072959ad2 
/home/USB\040HDD\040-\0404TB\040No\0407\040-\040Elements\040(EXT4)  ext4  
data=ordered,nofail                  0  0

# USB HDD - 4TB No 8 - My Passport
UUID=483ACC0A3ACBF2CC                     
/home/USB\040HDD\040-\0404TB\040No\0408\040-\040My\040Passport ntfs-3g
users,uid=1000,gid=1000,umask=022,big_writes,exec,defaults,noauto,nofail,x-systemd.automount,x-systemd.device-timeout=5
0 2


------------------------------------------------------------------------------------

 - FSTAB FILE WITH NORMAL DEFAUTLT NTFS MOUNT OPTIONS:

UUID=847c1296-1ff4-41b8-a0fb-a2be8d71857e  /          ext4  defaults      0  1
UUID=653E-9041                             /boot/efi  vfat  utf8          0  2
UUID=4c060c41-2a91-4b68-b01e-0102a78f1284  /home      ext4  data=ordered  0  2


# 320 GB USB HDD - NTFS Maxtor
#wait
#UUID=409C1078450547A4                     
/home/USB\040HDD\040-\040320GB\040-\040Maxtor  ntfs  
o,users,permissions,nofail                      0  0 &

# 320 GB USB HDD - NTFS - My Passport
#wait
#UUID=7858607050FA5558                     
/home/USB\040HDD\040-\040320GB\040-\040My\040Passport  ntfs  
o,users,permissions,nofail                      0  0 &

# 3TB No 1 USB HDD - NTFS - My Book
#wait
#UUID=655B2467153C6767                     
/home/USB\040HDD\040-\0403TB\040No\0401\040-\040My\040Book  ntfs  
o,users,permissions,nofail                      0  0  &

# 4TB No 1 USB HDD - NTFS - My Book
#wait
#UUID=67485E91550DB9F7                     
/home/USB\040HDD\040-\0404TB\040No\0401\040-\040My\040Book  ntfs  
o,users,permissions,nofail                      0  0 &

# 4TB No 2  USB HDD - NTFS - My Book
#wait
#UUID=3B575B303D8AA041                     
/home/USB\040HDD\040-\0404TB\040No\0402\040-\040(USB\0402)\040-\040My\040Book 
ntfs   o,users,permissions,nofail                      0  0 &

# 4TB No 3 - USB HDD - NTFS - My Book
#wait
#UUID=474E79A9081CE0F4                     
/home/USB\040HDD\040-\0404TB\040No\0403\040-\040My\040Book  ntfs  
o,users,permissions,nofail                      0  0 &

# 3TB No 2 USB HDD - EXT4 - My Book
#wait
#UUID=7ced6bd9-db96-4e0f-81f2-ce0ae8d41127 
/home/USB\040HDD\040-\0403TB\040No\0402\040-\040My\040Book\040(EXT4)  ext4  
data=ordered,nofail                  0  0 &

# 4TB No 4 - USB HDD - EXT4
#wait
#UUID=9247bf5f-fecb-4ef7-baee-79479be51d27 
/home/USB\040HDD\040-\0404TB\040No\0404\040-\040Elements\040(EXT4)   ext4     
data=ordered,nofail 0  0 &

# 4TB No 5 USB HDD - EXT4 - My Passport
#wait
#UUID=10f099e7-0f37-4a88-bac4-9526e142af76 
/home/USB\040HDD\040-\0404TB\040No\0405\040-\040My\040Passport\040(EXT4)  ext4 
 data=ordered,nofail                  0  0 &

# 4TB No 6 USB HDD - EXT4 - My Passport
#wait
#UUID=e52a9b33-4d3f-4231-8760-e35688814281
/home/USB\040HDD\040-\0404TB\040No\0406\040-\040My\040Passport\040(EXT4) ext4  
data=ordered,nofail 0  0 &

# 4TB No 7 - Elements SE - EXT4
#wait
#UUID=ff240d57-6269-4d86-8f8a-48d072959ad2 
/home/USB\040HDD\040-\0404TB\040No\0407\040-\040Elements\040(EXT4)  ext4  
data=ordered,nofail                  0  0 &


------------------------------------------------------------------------------------




REVIEW JOURNAL LOG FILE:
------------------------

sudo journalctl > log.txt
/var/log/journal/

Is showing MPEG Errors with File Krusader




HYPOTHESIS:
-----------

This is a timing issue - Variables to consider:

- Thumbnailer could be a Multi-Threaded Operation leading to multiple calls at
the same time
- Thumbnailer could have a built-in maximum time expenditure allowance per
thumnail creation - meaning it's possible that some thumbnails may not be
generated if the time expenditure is greater than allowed

-- 
You are receiving this mail because:
You are watching all bug changes.

Reply via email to