Hi. I'm getting a similar issue but it's related with the context menu from the tray icon. I'm the maintainer of prospect-mail but I also see this issue in https://super-productivity.com/ snap app.

This is the message:

abr 20 10:34:31 ubuntu-focal audit[584]: USER_AVC pid=584 uid=103 auid=4294967295 ses=4294967295 msg='apparmor="DENIED" operation="dbus_method_call"  bus="system" path="/" interface="org.freedesktop.DBus.ObjectManager" member="GetManagedObjects" mask="send" name="org.bluez" pid=31670 label="snap.prospect-mail.prospect-mail"
                                          exe="/usr/bin/dbus-daemon" sauid=103 hostname=? addr=? terminal=?'
abr 20 10:34:31 ubuntu-focal kernel: audit: type=1107 audit(1587396871.632:95874): pid=584 uid=103 auid=4294967295 ses=4294967295 msg='apparmor="DENIED" operation="dbus_method_call"  bus="system" path="/" interface="org.freedesktop.DBus.ObjectManager" member="GetManagedObjects" mask="send" name="org.bluez" pid=31670 label="snap.prospect-mail.prospect-mail"
                                      exe="/usr/bin/dbus-daemon" sauid=103 hostname=? addr=? terminal=?'
abr 20 10:34:32 ubuntu-focal dbus-daemon[2380]: apparmor="DENIED" operation="dbus_method_call"  bus="session" path="/com/canonical/dbusmenu" interface="org.freedesktop.DBus.Properties" member="GetAll" name=":1.14" mask="receive" pid=31670 label="snap.prospect-mail.prospect-mail" peer_pid=2846 peer_label="unconfined"
abr 20 10:34:32 ubuntu-focal dbus-daemon[2380]: apparmor="DENIED" operation="dbus_method_call"  bus="session" path="/com/canonical/dbusmenu" interface="com.canonical.dbusmenu" member="AboutToShow" name=":1.14" mask="receive" pid=31670 label="snap.prospect-mail.prospect-mail" peer_pid=2846 peer_label="unconfined"
abr 20 10:34:32 ubuntu-focal dbus-daemon[2380]: apparmor="DENIED" operation="dbus_method_call"  bus="session" path="/com/canonical/dbusmenu" interface="com.canonical.dbusmenu" member="GetLayout" name=":1.14" mask="receive" pid=31670 label="snap.prospect-mail.prospect-mail" peer_pid=2846 peer_label="unconfined"
abr 20 10:34:32 ubuntu-focal <email address hidden>[2846]: Impossible to send about-to-show to menu: Gio.DBusError: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: An AppArmor policy prevents this sender from sending this message to this recipient; type="method_call", sender=":1.14" (uid=1000 pid=2846 comm="/usr/bin/gnome-shell " label="unconfined") interface="com.canonical.dbusmenu" member="AboutToShow" error name="(unset)" requested_reply="0" destination=":1.783" (uid=1000 pid=31670 comm="/snap/prospect-mail/x1/prospect-mail --no-sandbox " label="snap.prospect-mail.prospect-mail (enforce)")
abr 20 10:34:32 ubuntu-focal <email address hidden>[2846]: While reading menu layout on proxy ':1.783: Gio.DBusError: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: An AppArmor policy prevents this sender from sending this message to this recipient; type="method_call", sender=":1.14" (uid=1000 pid=2846 comm="/usr/bin/gnome-shell " label="unconfined") interface="com.canonical.dbusmenu" member="GetLayout" error name="(unset)" requested_reply="0" destination=":1.783" (uid=1000 pid=31670 comm="/snap/prospect-mail/x1/prospect-mail --no-sandbox " label="snap.prospect-mail.prospect-mail (enforce)")