I got a very similar error message on the gnome-tweaks part of my bug
report, and it can be considered a duplicate of that issue.
$ gnome-tweaks
** (..gnome-tweaks-real-real:2189): WARNING **: 11:47:39.372: Failed to load
shared library 'libsoup-2.4.so.1' referenced by the typelib: libsoup-2.4.so.1:
cannot open shared object file: No such file or directory
WARNING : Error detecting shell
Traceback (most recent call last):
File
"/gnu/store/mclwkx5n56ki3fqp1rnwxnwvg2nk8s8j-gnome-tweaks-3.28.1/lib/python3.7/site-packages/gtweak/tweaks/tweak_group_shell_extensions.py",
line 219, in __init__
ego = ExtensionsDotGnomeDotOrg(version)
File
"/gnu/store/mclwkx5n56ki3fqp1rnwxnwvg2nk8s8j-gnome-tweaks-3.28.1/lib/python3.7/site-packages/gtweak/egowrapper.py",
line 25, in __init__
self._session = Soup.Session.new()
GLib.GError: g-invoke-error-quark: Could not locate soup_session_new:
libsoup-2.4.so.1: cannot open shared object file: No such file or directory (1)
WARNING : Error detecting shell
Traceback (most recent call last):
File
"/gnu/store/mclwkx5n56ki3fqp1rnwxnwvg2nk8s8j-gnome-tweaks-3.28.1/lib/python3.7/site-packages/gtweak/tweaks/tweak_group_shell_extensions.py",
line 53, in __init__
self._swInfo = Gio.DesktopAppInfo.new("org.gnome.Software.desktop")
TypeError: constructor returned NULL
$