Invisible vsdiff in Fedora 42 under KDE Plasma 6.5

[MysteryGuy]

Hi;

I'm using Slickedit Pro 28.0.2.0 under Fedora 42 with the KDE desktop.

Things were working o.k. under KDE Plasma 6.4.5. But Fedora just updated to KDE 6.5.

I now have a very strange problem. Running vs_exe seems to work fine to do editing. Performing a vsdiff from within Slickedit seems to work o.k. as well.

But if I run vsdiff from the command line, more often than not the slickedit vsdiff appears to run as an invisible window. As in it appears to be there but I just can't see it. I do first see the dialog asking about what files to diff and that comes up reliably. But when I actually select the 'diff' button then the dialog goes away, but I can not see the diff window. It does not appear to prevent the view of what is presumably behind the window either as I can see the desktop.

It seems to be able to respond to commands as I once hit 'Control-R' thinking I was working in a command line and it seems to have gone to the vsdiff instead. I saw a window pop-up complaining "Command 'record-macro-toggle' is not allowed in diff mode".

But, sometimes it seems to come up normally (and visible). It's almost as if there is some sort of race going on.

Any idea on how to debug or fix this?

Running xprop or xwininfo (from a different command-line) with the '-name "DIFFzilla(R) Pro"' does find information for the window (although I don't know how helpful that is).

[Clark]

Post your Help>About SlickEdit... information

[Dan]

Hi;

I'm using Slickedit Pro 28.0.2.0 under Fedora 42 with the KDE desktop.

Things were working o.k. under KDE Plasma 6.4.5. But Fedora just updated to KDE 6.5.

I now have a very strange problem. Running vs_exe seems to work fine to do editing. Performing a vsdiff from within Slickedit seems to work o.k. as well.

But if I run vsdiff from the command line, more often than not the slickedit vsdiff appears to run as an invisible window. As in it appears to be there but I just can't see it. I do first see the dialog asking about what files to diff and that comes up reliably. But when I actually select the 'diff' button then the dialog goes away, but I can not see the diff window. It does not appear to prevent the view of what is presumably behind the window either as I can see the desktop.

It seems to be able to respond to commands as I once hit 'Control-R' thinking I was working in a command line and it seems to have gone to the vsdiff instead. I saw a window pop-up complaining "Command 'record-macro-toggle' is not allowed in diff mode".

But, sometimes it seems to come up normally (and visible). It's almost as if there is some sort of race going on.

Any idea on how to debug or fix this?

Running xprop or xwininfo (from a different command-line) with the '-name "DIFFzilla(R) Pro"' does find information for the window (although I don't know how helpful that is).

It it possible that it is visible, but off the screen? Particularly if you changed from an external monitor to a notebook screen, for instance.

[MysteryGuy]

Post your Help>About SlickEdit... information

I am running in a VM and have since reverted to an earlier Fedora 42 snapshot from before the Plasma updates. (Since I need to use my system).

But I did previously try upgrading my Fedora 42 to Fedora 43 just to see if that was any different (It did not seem to make a difference here). This has (in theory) the same level of KDE Plasma (I believe) as the updated Fedora 42 version.

I still have that snapshot after updating to Fedora 43. So I fired it up and did 'About' from there. I will put it at the end here (I didn't see how to add an attachment). I have blanked out the license number and home directory name.

If needed, I can again update my current Fedora 42 to the latest Fedora 42 updates  (including the newer KDE Plasma updates).
 

Code: [Select]

SlickEdit Pro 2023 (v28.0.2.0 64-bit Qt4)

Serial number: VLX-----
Licensed number of users: Single user
License file: /home/----/slickedit-pro2023/bin/slickedit.lic

Build Date: April 3, 2024
Emulation: SlickEdit (text mode edition)

OS: Linux
OS Version: Fedora Linux 43 (KDE Plasma Desktop Edition)
Kernel Level: 6.17.8-300.fc43.x86_64
Build Version: #1 SMP PREEMPT_DYNAMIC Fri Nov 14 01:47:12 UTC 2025
Processor Architecture: x86_64

X Server Vendor: The X.Org Foundation
Window Manager: KWin (XWayland)
Display manager: /usr/bin/sddm

Memory: 19% Load, 3268MB/17163MB Virtual
Shell Information: "/home/----/slickedit-pro2023/bin/secsh" -i
Screen Size: 1707 x 960 (0 0)

Project Type: Single file project - Other
Language: .txt (Plain Text)
Encoding: UTF-8, no signature

Installation Directory: /home/----/slickedit-pro2023/
Configuration Directory: /home/----/.slickedit/28.0.2/
Imported options from: 28.0.2.0


[MysteryGuy]

...

It it possible that it is visible, but off the screen? Particularly if you changed from an external monitor to a notebook screen, for instance.
[/quote]

I'm not sure. Although I use only one screen and don't switch resolutions, etc.

And this sometimes works and sometimes doesn't without any apparent rhyme or reason that I can see. And I've only seen vsdiff  fail when launching from the command line.

[Clark]

Download and install the 64-bit linux Qt5 installer:

se_28000200_linux64qt5.tar.gz

That should make things work a lot better.

In general, the Qt5 installer works better on newer Linux systems. The Qt4 installer is needed for really old Linux systems. Bottom line, use the one which works better on your Linux.

[MysteryGuy]

Download and install the 64-bit linux Qt5 installer:

se_28000200_linux64qt5.tar.gz

That should make things work a lot better.

In general, the Qt5 installer works better on newer Linux systems. The Qt4 installer is needed for really old Linux systems. Bottom line, use the one which works better on your Linux.

Thank you! That seems to work much better reliably launching vsdiff (at least with my 'exhaustive' 2 minute test...  ).

I do see something unusual that I don't understand when launching from the command line though.

When I launch vs_exe or vsdiff from the command line I see:

Code: [Select]


] /home/----/slickedit-pro2023/bin/vsdiff

qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""
QFont::fromString: Invalid description 'Droid Sans,10,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'
QFont::fromString: Invalid description 'IBM Plex Mono,10,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'
QFont::fromString: Invalid description 'Droid Sans,10,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'
QFont::fromString: Invalid description 'Droid Sans,9,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'


I don't know exactly what that's trying to tell me. (The Qfont complaints might have already been there, but the qt.qpa.plugin: is new I think).

 Those font names match some of the names of the 'default' KDE fonts that you can specify in the KDE 'System Settings' / 'Text & Fonts' settings.

These fonts are all installed as best as I can tell.

Based only on a google search I tried launching vsdiff with some 'debug' options for QT.

Code: [Select]

] QT_DEBUG_PLUGINS=1 /home/----/slickedit-pro2023/bin/vsdiff

which produced a boatload of stuff including the suspicious looking things

Code: [Select]

Got keys from plugin meta data ("xcb")
qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""
loaded library "/home/----/slickedit-pro2023/bin/platforms/libqxcb.so"

...

Got keys from plugin meta data ("xdgdesktopportal", "flatpak", "snap")
QFont::fromString: Invalid description 'Droid Sans,10,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'
QFont::fromString: Invalid description 'IBM Plex Mono,10,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'
QFont::fromString: Invalid description 'Droid Sans,10,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'
QFont::fromString: Invalid description 'Droid Sans,9,-1,5,400,0,0,0,0,0,0,0,0,0,0,1'
...
loaded library "/home/----/slickedit-pro2023/bin/imageformats/libqjpeg.so"
Cannot load library /home/----/slickedit-pro2023/bin/imageformats/libqmng.so: (libmng.so.1: cannot open shared object file: No such file or directory)
QLibraryPrivate::loadPlugin failed on "/home/----/slickedit-pro2023/bin/imageformats/libqmng.so" : "Cannot load library /home/----/slickedit-pro2023/bin/imageformats/libqmng.so: (libmng.so.1: cannot open shared object file: No such file or directory)"
loaded library "/home/----/slickedit-pro2023/bin/imageformats/libqtga.so"


So as best as I can see a slickedit .so failed to load because it was unable to find the shared object "libmng.so.1" that it referenced.

I can see that on my system I do have a libmng.so.2, but not a libmng.so.1.

Code: [Select]

] locate libmng.so.2

/usr/lib64/libmng.so.2
/usr/lib64/libmng.so.2.0.2

]  locate libmng.so.1
]

I don't know if that's why the complaints on launch pop up or not. I wonder if 'libmng.so.1' is an older version?

Any idea what's going wrong?

Thanks.

[Clark]

I've uploaded a few shared libraries to this drop box folder:

https://www.dropbox.com/scl/fo/5mx2nypw42fbvmwo0mk0k/AFCxHGAcxu7HPe8hXeXtQgM?rlkey=flqxijynwy0fuv9iwpx79uz74&st=18ss2b2a&dl=0

Download libmng.so.1, liblcms.so.1 and libjpeg.so.62

Put them all in the "<slickedit-root-install-dir>/bin" directory.

That should allow libqjpeg.so to load. Not sure if this will effect the odd QFont::fromString errors. I wasn't able to reproduce that.

Let us know how this works for you.

Thanks for all the details on this issue.