copy/paste not working

[Ralf Mardorf]

PS:

1. I finished my Arch Linux session and booted Ubuntu 16.04.
2. Ctrl+Alt+H shows that the history of parcellite is empty.
3. From qupzilla's address bar I copied the following URL into this
claws-mail message: https://www.startpage.com/
4. qupzilla and parcellite are from official Ubuntu repos and I could
install plasma-workspace without issues:

[weremouse at moonstudio ~]$ lsb_release -a
LSB Version:	core-9.20160110ubuntu0.2-amd64:core-9.20160110ubuntu0.2-noarch:security-9.20160110ubuntu0.2-amd64:security-9.20160110ubuntu0.2-noarch
Distributor ID:	Ubuntu
Description:	Ubuntu 16.04.6 LTS
Release:	16.04
Codename:	xenial
[weremouse at moonstudio ~]$ apt -qq list parcellite qupzilla
parcellite/xenial,now 1.1.9-1 amd64 [installed]
qupzilla/xenial,now 1.8.9~dfsg1-3 amd64 [installed]
[weremouse at moonstudio ~]$ sudo apt install plasma-workspace
[snip]
0 upgraded, 191 newly installed, 0 to remove and 0 not upgraded.
Need to get 51.9 MB of archives.
After this operation, 259 MB of additional disk space will be used.
Do you want to continue? [Y/n] n
Abort.
[weremouse at moonstudio ~]$

My environment:

[weremouse at moonstudio ~]$ wmctrl -m
Name: Openbox
Class: 
PID: N/A
Window manager's "showing the desktop" mode: OFF

Marginalia:

qupzilla is that old, that it fails to work when using startpage,
google still works. However, copy and paste is no issue at all.

Note! I build some packages myself, e.g. claws, so I can share all
settings and POP account mails with my Arch Linux install or e.g.
lxpanel, when the weather plugin service was discontinued, the official
Ubuntu repositories never received an upgrade providing the
plugin, using another weather service. IOW I fixed the borked lxpanel.

$ dpkg -l claws-mail-git lxpanel | grep ii
ii  claws-mail-git 3.17.3-1     amd64        A GTK+ based e-mail client - git checkout
ii  lxpanel        0.10.0-1     amd64        LXDE panel

Those are applications with minimal dependencies and I know what I'm
doing. I don't break my install, I enhance or sometimes even fix the
install, if Ubuntu maintainers do not fix issues.

However, doing this with something bloated, such as KDE is more or less
impossible.