Comment # 1 on bug 1040433 from Marguerite Su

Sorry for the so late reply.

But the good news is I reply with the cause found :-D

In /usr/bin/retext we have a line:

inputData = '' if (sys.stdin is None or sys.stdin.isatty()) else
sys.stdin.read()

which means if the standard input pipe got an invalid file descriptor (the only
None case) or we are running retext from command line, inputData will be an
empty placeholder. if not, it will read from the standard input pipe for a file
name.

Unluckily sys.stdin.read() is a blocking action. it will not end until
receiving inputs. And Of course we can't give it inputs while starting it from
a click on the desktop. But if you run retext from command line, it'll be fine
because stdin was not read at all.