I should have included in the original bug report that starting
pcmanfm-qt from a terminal emulator results in the following:
----------------------------8<----------------------------
** Message: x-terminal-emulator has very limited support,
consider choose another terminal
** (process:6455): WARNING **: XDG_TEMPLATES_DIR is set to
invalid path, ignoring it
----------------------------8<----------------------------
I realize that this means that something is wrong with the
environment, but I haven't had to explore the cause or try
correcting it.
Please advise.
Thanks.