Denis Auroux - 2019-06-21

  1. Can you explain what happens after those first few seconds when
    things work ok -- does the touch then start drawing with the pen? does
    it not do anything at all? when you try to use the touchscreen while
    it's not working anymore, does the pen/pencil icon remain selected, or
    has the toolbar selection changed to something else?

  2. Can you please provide the output of the command "xinput list" ?

2'. (Not sure if this is applicable to Ubuntu): If at the login screen
you have a choice, in the list of session types, between running Gnome
over Xorg vs. over Wayland, please run it over Xorg -- the Xwayland
interface for pen input in X applications over Wayland has only recently
begun to work properly with GTK2 applications such as xournal, and I
don't know if your distribution is recent enough for xournal to work
well over Xwayland.

  1. Does the problem persist if you use a newer version, namely download
    and compile version 0.4.8.2016 from xournal.sourceforge.net or get the
    latest GIT code repository? (either one should be fine)

(Regarding #3, if you don't want to needlessly uninstall the ubuntu
package, just download the code, compile [./autogen.sh ; watch for any
missing development packages that may need to be installed, re-run
./configure until it looks successful; make] but do not "make install",
instead just go to the src directory and run ./xournal there. Of course
if this fixes the issue then I recommend uninstalling the ubuntu package
and running (as root) "make install; make desktop-install" to install
the version you compiled).

Sorry to not be more helpful -- this isn't very much information to go with.

Denis