Unable to start prebuild because of missing xcb plugin

[Chunosov]

This application failed to start because it could not find or load the Qt platform plugin "xcb"
in "".

Available platform plugins are: xcb.

Reinstalling the application may fix this problem.
Aborted (core dumped)

The issue is similar to the problem other project have experienced, e.g nextcloud/desktop#235 or drawpile/Drawpile#636.

Seems the problem appeared with one of Ubuntu updates. I have AppImage of another project built before I've updated to Ubuntu 18 and it's able to run on the same system when this app is failed. But when I've rebuilt that AppImage now, it fails with the same error. Maybe it has a sense to try building AppImage on some older Ubuntu distro (16 LTS ?).

There is recommendation (nextcloud/desktop#235) remove libharfbuzz.so.0 and/or libfreetype.so.6 from the bundle, but we have't them there.

[probonopd]

Please build what goes into AppImages on the oldest still-supported LTS release to ensure that the resulting AppImage will run on all still-supported LTS releases. Currently that is Ubutnu 14.04 (trusty).

https://docs.appimage.org/packaging-guide/ingredients.html?highlight=oldest#binaries-compiled-on-old-enough-base-system

[probonopd]

You can use services like Travis CI or GitLab CI to do the builds, so you don't have to install a specific version of Linux on your desktop machine. See https://github.com/probonopd/linuxdeployqt#using-linuxdeployqt-with-travis-ci for an example.