Report Bugs

Bugs happen. That is a fact. But they can be fixed. And the better a bug report is the easier it is for the development team to replicate, investigate, and eventually fix it.

All bug reports need to be logged in the official bug tracker. And feature requests are tracked there as well using the severity item wishlist. But before you do, please do the following:

Step 1: Upgrade to the latest release

Please upgrade to the latest released versions of Kdenlive. We do not answer bug reports for old Kdenlive versions (unless they are still reproducible in latest version).

Step 2: Search the official Kdenlive documentation

RTFM - Read The Fine Manual is a phrase often used to mock users asking questions that could be answered by reading the documentation. In the days and age of YouTube tutorial this may not be as important or relevant anymore, but you are encouraged to consult the official Kdenlive documentation. It can be searched and contains a wealth of good and valuable information.

Step 3: Search the forums

Kdenlive has a large community that is active in forums and chat rooms. Check the official forum whether other users encountered the same issue. Perhaps a fix or workaround exists. Other channels to check are

Step 4: Query open issues

Search the bug tracker. Perhaps the issue you are experiencing has already been reported or is even worked on. The bug's status is a good indicator for what is currently happening:

  • REPORTED is a bug that has been reported but nothing has happened so far. There may be a discussion about it, so it is worth checking if it may apply to your issue.
  • NEEDSINFO is a reported bug, which needs more feedback. This means, a dev team member looked at it but needs more details
  • CONFIRMED means that the bug can be reproduced (either by other users or the dev team)
  • ASSIGNED means that a developer is handling the bug
  • RESOLVED means that the bug was fixed in the development version

Step 5: Report the bug

If you have a crash at Kdenlive startup or when trying to play a video file, please follow this steps:

  1. If you compiled Kdenlive and/or MLT yourself, make sure you followed all steps described in our instructions.
  2. Check that you don’t have several versions of MLT installed
  3. Try playing your video file with FFmpeg’s player. From a terminal: ffplay myvideo.mpg
  4. Try playing your video file with MLT’s player. From a terminal: melt myvideo.mpg

Include the results in your bug report as attachments.

For a good bug report please include the following information:

  • Your Kdenlive and MLT version. You can copy that information from Kdenlive Menu > Help > About.
  • Your operating system (OS), like Windows, Linux distro, or MacOS including the respective version
  • The installation method for Kdenlive, like Windows installer or standalone, or Linux flatpak/snap/ppa or appimage
  • Detailed steps to reproduce the bug. Screenshots and screen recordings are very useful for replicating the issue.
  • Any error messages or log files you can provide. Please do not copy & paste log content into the bug report but add it as an attachment.
  • If the bug crashes Kdenlive, provide a backtrace.

How to get useful crash information (backtrace)

A backtrace contains valuable information for the dev team. It needs a bit of OS specific setup and command line wizardy and may therefore be not everyone's cup of tea.

Linux appimage

Please install the following packages: gdb, kdenlive-dbg, libmlt-dbg (package names may be slightly different depending on your distro)

When Kdenlive crashes, if the KDE crash handler dialog pops up, you can copy the data it provides. Otherwise, start Kdenlive from a terminal like this:

  1. Type gdb kdenlive
  2. After gdb read debug symbols, type run

Linux Flatpak

First of all make sure the Flatpak debug symbols are installed by typing flatpak install org.kde.kdenlive.Debug to a command line.

Now you can start the Flatpak from a command line like this:

  1. Start a shell inside the Kdenlive Flatpak sandbox: flatpak run --command=sh --devel org.kde.kdenlive
  2. Type gdb /app/bin/kdenlive
  3. After gdb read debug symbols, type run

For more details on Flatpak debugging see here: https://docs.flatpak.org/en/latest/debugging.html

Windows

  1. Build Kdenlive with KDE Craft locally as described here.
  2. Type to the command line cd C:/CraftRoot/mingw64/bin
  3. Start gdb with gdb
  4. Start Kdenlive -> get the PID number
  5. attach 3288 (replace 3288 by the PID number)
  6. Wait on the (gdb) prompt
  7. Type c

Once you followed the platform specific instructions above to start Kdenlive, you can trigger the bug. When Kdenlive crashes, go to your terminal window and type:

thread apply all bt full

Then press enter until you see the full data. Copy the log to a file and attach it to the bug report.