Created attachment 184638 [details] Tests & Conclusions & Ruled out Possibilities SUMMARY Krusader - Intermittant Displaying Previews of 'Folder' Thumbnails on NTFS Drives/Partitions STEPS TO REPRODUCE 1. Using Krusader have Previews on, and goto an NTFS Drive/Partition with videos on it (root or folder) OBSERVED RESULT Observe any/all 'Folders' to see the thumbnails being generated on them Note that many folders will never show any thumbnails despite the folder having videos in it EXPECTED RESULT All folders that have at least 1 video in them should display at least 1 video thumbnail on the folder SOFTWARE/OS VERSIONS File Krusader v2.9.0 "Sixth Life" - RPM Installation KDE INFO: Operating System: openSUSE Tumbleweed 20250820 KDE Plasma Version: 6.4.4 KDE Frameworks Version: 6.17.0 Qt Version: 6.9.1 Kernel Version: 6.16.1-1-default (64-bit) Graphics Platform: Wayland Processors: 12 × 11th Gen Intel® Core™ i5-11500 @ 2.70GHz Memory: 32 GiB of RAM (31.2 GiB usable) Graphics Processor: AMD Radeon RX 6600 Manufacturer: Gigabyte Technology Co., Ltd. Product Name: H510M DS2V ADDITIONAL INFORMATION: Dolphin file manager v25.08.0 also has this issue I have included an attachment text file which is a list of various tests and things i have been able to rule out as related to this
Created attachment 184657 [details] screenshot of folder thumbnails
Please note, Im not talking about the actual video file thumbnails themselves, they display fine 100% guaranteed all the time perfectly Im referring to the actual 'Folder' icon itself, that normally would display 4 separate thumbnails on the folder icon itself if the folder has at least 4 video files in it I have folders with mixed video file types
Cloud Link to the strace_output.txt file (4.7 GB) https://mega.nz/file/dKYxWKIK#FSNZpdz89iICa_tkuO_LMqwp14LsE-6Bl1HN_9WrYBw
> Dolphin file manager v25.08.0 also has this issue Ben, that behavior is not caused by the source code of Krusader. Perhaps it will be more useful for you to change to "Dolphin" the "Product" of this bug report, maybe they will help you better with this.
Comment on attachment 184638 [details] 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